Answer:
The hikers average speed due north is 0.2 km per minute.
Explanation:
Speed is the ratio of distance moved by a body to the time taken.
i.e speed = [tex]\frac{distance}{time}[/tex]
Since the hiker walks due north and due west, then his average speed due north can be determined by;
Average speed = [tex]\frac{total distance due north}{total time taken}[/tex]
Total distance due north = 5.0 + 7.0
= 12.0 km
Total time taken = 20 + 40
= 60 minutes
= 1 hour
Average speed due north= [tex]\frac{12}{60}[/tex]
= [tex]\frac{1}{5}[/tex]
= 0.2
Average speed due north = 0.2 km/minute
The hikers average speed due north is 0.2 km per minute.
Please help i will give brainliest
Answer:
Answers below--
Explanation:
1. F/Force
2.H/Contact force
3.A/Non-contact force
4.C/electric force
5.D/gravity
6.I(i)/magnetic force
7.J/kilogram
8.G/newton
9.B/friction
10.E/lubricant
Hi!! Does anyone know this answer? :D
Answer:
Im not fully corrrect but I would say C
Explanation:
The driver of a 1.5 x 103 kg car is traveling east at 10 m/s and increases its speed to 30 m/s east over 15 seconds. What was the change in momentum of the car? Kgm/s
Answer:
30,000kgm/s
Explanation:
Change in momentum is expressed as;
Change in momentum = mass × change in velocity
∆M = m∆v
Mass m = 1.5×10³kg = 1500kg
∆v = 30-10 =20m/s
Substitute into the formula
Change in momentum = 1500(20)
Change in momentum = 30,000kgm/s
How many moons are in our solar system?
A wave has frequency of 50 Hz and a wavelength of 10 m. What is the speed of the wave? Group of answer choices
Explanation:
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How much work is done if a force of 20 N is used to move an object 6 meters
Explanation:
W=f×d
=20×6
w=120 joule
How high did a worker lift a 25 kg bag of sand if it now has 2940 of gravitational potential energy
Answer:
12 m
Explanation:
From the question given above, the following data were obtained:
Mass (m) of bag = 25 kg
Potential energy (PE) = 2940 J
Height (h) =?
Objects carried to a particular height will always experience an acceleration due to gravity of 9.8 m/s².
With the above in mind, we can obtain the height to which the load is lifted to as shown below:
Mass (m) of bag = 25 kg
Potential energy (PE) = 2940 J
Acceleration due to gravity (g) = 9.8 m/s².
Height (h) =?
PE = mgh
2940 = 25 × 9.8 × h
2940 = 245 × h
Divide both side by 245
h = 2940 / 245
h = 12 m
Therefore, the worker lifts the load to a height of 12 m.
Marina walked 2km in half an hour, what was her average speed during her walk?
Answer:
4km/hr
Explanation:
Fig. 2.1 shows a train
Fig. 2.1
The total mass of the train and its passengers is 750000kg. The train is travelling at a speed of 84m/s.
The driver applies the brakes and the train takes 80s to slow down to a speed of 42m/s.
(a) Calculate the impulse applied to the train as it slows down,
impulse =
[3]
(b) Calculate the average resultant force applied to the train as it slows down,
force =
(2)
Answer:
[tex]\mathrm{(a)\:}32,000,000\:\mathrm{Ns},\\\mathrm{(b)\:}390,000\:\mathrm{N}[/tex]
Explanation:
The impulse-momentum theorem states the impulse on an object is equal to the change in momentum of that object. Momentum is given by [tex]p=mv[/tex]. Since mass is constant, the train's change in momentum is:
[tex]\Delta p=m\Delta v=750,000\cdot42=31,500,000=\fbox{$32,000,000\:\mathrm{Ns}$}[/tex](two significant figures).
Impulse is also given as [tex]\Delta p = F\Delta t[/tex], where [tex]F[/tex] is the average force applied and [tex]\Delta t[/tex] is change in time. Since [tex]t[/tex] is given as [tex]80\mathrm{s}[/tex], we have the following equation:
[tex]F\Delta t=\Delta p\\\\F=\frac{\Delta p}{\Delta t},\\\\F=\frac{31,500,000}{80},\\\\F=393,750=\fbox{$390,000\:\mathrm{N}$}[/tex](two significant figures).
a train has an initial velocity of 44m/s and an accelaration of _4m/s calculate its velocity
Answer:
It's 4m/s
Explanation:
V = u _ at, at u = 44m/s
44 + [-4]10
4m/s
You blow up a balloon but don't tie it. When you let it go, it flies around the room.
Which of Newton's Laws does the scenario describe?
1st Law
2nd Law
3rd Law
Answer:
3rd law beacuse there a flies
On Earth, a spring stretches by 5.0 cm when a mass of 3.0 kg is suspended from one end.
The gravitational field strength on the Moon is
1/6 of that on Earth.
Which mass, on the Moon, would stretch the spring by the same extension?
Reasons too :(
igcse physics
Answer:
Mass = 18.0 kg
Explanation:
From Hooke's law,
F = ke
where: F is the force, k is the spring constant and e is the extension.
But, F = mg
So that,
mg = ke
On the Earth, let the gravitational force be 10 m/[tex]s^{2}[/tex].
3.0 x 10 = k x 5.0
30 = 5k
⇒ k = [tex]\frac{30}{5}[/tex] ................ 1
On the Moon, the gravitational force is [tex]\frac{1}{6}[/tex] of that on the Earth.
m x [tex]\frac{10}{6}[/tex] = k x 5.0
[tex]\frac{10m}{6}[/tex] = 5k
⇒ k = [tex]\frac{10m}{30}[/tex] ............. 2
Equating 1 and 2, we have;
[tex]\frac{30}{5}[/tex] = [tex]\frac{10m}{30}[/tex]
m = [tex]\frac{900}{50}[/tex]
= 18.0
m = 18.0 kg
The mass required to produce the same extension on the Moon is 18 kg.
Answer:
18 kg
Explanation:
weight (N) = mass (kg) × gravitational acceleration (m/s²)force (N) = k (spring constant) × extension (m)On Earth, acceleration of gravity is 10 m/s²
weight = 3.0 (kg) × 10 (m/s²)weight = 30 (N)Since weight is a force, the force is 30 N. The value of spring constant is unknown
30 (N) = k × 5 (m)k = 6 (m/N)Spring constant is 6. Now let's find the mass on the Moon
mass (kg) × gravitational acceleration (m/s²) = k (spring constant) × extension (m)Gravitational acceleration of the moon is 1/6 of that on Earth. Earth's g = 10, so Moon's g = 10/6
m × 10/6 = 6 × 5m = 30/(10/6)m = 18The mass is 18 kg
A wave that can travel through empty space?
A. electromagnetic wave
B. mechanical wave
C. compressional wave
D. transverse wave
Answer: B. Mechanical Waves
Explanation:
If the boy travelled 2 meters to the right and 4 meters to the left what is the total distance that he travelled?
4 m
-4 m
6 m
2 m
Answer:
6m
Explanation:
2+4=6
Metals are good conductors of heat because .
Answer:
They have the highest melting point so that mean that the temperature and the are a conductive to electricity.
Explanation:
A horizontal pole is attached to the side of a building. There is a pivot P at the wall and a chain is connected from the end of the pole to a point higher up the wall. There is a tension force F in the chain. What is the moment of the force F about the pivot P?
Answer:
Fscos63
Explanation:
Given that a horizontal pole is attached to the side of a building. There is a pivot P at the wall and a chain is connected from the end of the pole to a point higher up the wall. There is a tension force F in the chain. What is the moment of the force F about the pivot P?
Taking the moment from the pivot point P, that means the moment at point p = 0
Then, if we consider the weight mg of the pole, according to the principle of equilibrium : sum of the upward forces equal to the sum of the downward forces.
Therefore, mg = Fsinø ....... (1)
Also, taking moment at point P
Let the length of the pole = s
The length of the weight of the pole = 1/2 S
Fscosø = mgs/2
The distance s will cancel out
2Fcosø = mg ...... (3)
Substitute mg in equation 1 into equation 3
2fcosø = fsinø
F will cancel out
Tanø = 2
Ø = tan^-1(2)
Ø = 63.4 degree
The moment of force F about pivot point P will be
Moment = force × distance
Moment = Fcos63 × S
Moment = Fscos63
At the height of 800 meters, a skydiver falls from an airplane flying horizontally at 40 m/sec. What is the horizontal distance of the skydivers travel before they "hit" the ground?
Answer:
The horizontal distance traveled by the skydiver is 510.8 m.
Explanation:
Given;
height of fall, h = 800 m
initial velocity of the airplane, u = 40 m/s
The time to fall to the ground is calculated as;
[tex]t = \sqrt{\frac{2h}{g} } \\\\t = \sqrt{\frac{2 \times 800}{9.81} }\\\\t = 12.77 \ s[/tex]
The horizontal distance or range of the motion is calculated as;
R = ut
R = 40 m/s x 12.77 s
R = 510.8 m
Therefore, the horizontal distance traveled by the skydiver is 510.8 m.
A boat traveling across a river has a resultant velocity of 10 km/h and travels 34 degrees with respect to the shore. A) What is the boats velocity in m/s?
B) What is the velocity of the river in m/s?
Answer:
a) 1.55 m/s
b) 2.3 m/s
Explanation:
We know that the boat travels across the river, if we define the river as the x-axis, then the velocity of the boat is only on the y-axis.
Then we can write the velocity of the boat in still water as:
S = (0, B)
Now, when the boat is on the river, the velocity of the boat will be equal to the velocity of the boat in still water plus the velocity of the river.
The velocity of the river is:
v = (R, 0).
Then the velocity of the boat in that river is:
V' = (0, B) + (R, 0) = (R, B)
Now, we know that the velocity of the boat is 10km/h, and it travels at an angle of 34° with respect to the shore.
We can use the Pythagoreans theorem to write the components of this velocity as:
x-axis component = 10km/h*cos(34°) = 8.29 km/h
y-axis component = 10km/h*sin(34°) = 5.59 km/h
Then the velocity of the boat can be written in components as:
velocity = ( 8.29 km/h, 5.59 km/h)
And we knew that the velocity of the boat was written as (R, B)
Then we must have:
R = 8.29 km/h
B = 5.59 km/h
a) The speed of the boat in m/s:
We know that the speed of the boat is 5.59 km/h.
First, we know that:
1km = 1000m, then:
5.59 km/h = 5.59*(1000m)h = 5,590 m/h
And we know that:
1h = 3600s
Then we can write:
5,590 m/h = 5,590 m/(3600s) = 1.55 m/s
b) The speed of the river in m/s:
We know that the speed of the river is 8.29 km/h
Using the same reasoning as above, we can do the change of units as follows:
8.29 km/h = 8.29 (1000m)/(3600s) = 2.3 m/s
what is projectile. what is projectile motion
The projectile is any object thrown into space upon which the only acting force is gravity. In other words, the primary force acting on a projectile is gravity. This doesn’t necessarily mean that the other forces do not act on it, just that their effect is minimal compared to gravity. The path followed by a projectile is known as a trajectory. A baseball batted or thrown and the instant the bullet exits the barrel of a gun are all examples of the projectile.
Projectile Motion:When a particle is thrown obliquely near the earth’s surface, it moves along a curved path under constant acceleration that is directed towards the center of the earth (we assume that the particle remains close to the surface of the earth). The path of such a particle is called a projectile and the motion is called projectile motion. Air resistance to the motion of the body is to be assumed absent in projectile motion.
In a Projectile Motion, there are two simultaneous independent rectilinear motions:
Along the x-axis: uniform velocity, responsible for the horizontal (forward) motion of the particle.
Along y-axis: uniform acceleration, responsible for the vertical (downwards) motion of the particle.
Accelerations in the horizontal projectile motion and vertical projectile motion of a particle: When a particle is projected in the air with some speed, the only force acting on it during its time in the air is the acceleration due to gravity (g). This acceleration acts vertically downward. There is no acceleration in the horizontal direction, which means that the velocity of the particle in the horizontal direction remains constant.
[tex]\sf~~~~~~~~~~~~~~~{\red{\underbrace{\underline{\green{projectile~motion}}}}}[/tex]
Projectile motion is a form of motion in which object or particle is thrown near earth's surface and it moves along a curved path under the action of gravity only.
A lift travelling up to the top floor of the Empire State building with a mass of 4200kg and a kinetic energy of 4116J. Find the velocity
Answer:
1.4 m/sExplanation:
The velocity can be found by using the formula
[tex]v = \sqrt{ \frac{2k}{m} } \\ [/tex]
k is the kinetic energy
m is the mass
From the question we have
[tex]v = \sqrt{ \frac{2 \times 4116}{4200} } \\ = 1.4[/tex]
We have the final answer as
1.4 m/sHope this helps you
Answer:
The speed of the lift is 1.4 m/s
Explanation:
Kinetic Energy
Is the type of energy of an object due to its motion. It's proportional to the square of the speed and the mass.
The equation for the kinetic energy is:
[tex]\displaystyle K=\frac{1}{2}mv^2[/tex]
Where:
m = mass of the object
v = speed at which the object moves
The kinetic energy is expressed in Joules (J)
It's given the mass of the lift as m=4,200 kg and its kinetic energy K=4,116 J. To calculate the speed (magnitude of velocity), we solve the formula for v as follows:
[tex]\displaystyle v=\sqrt{\frac{2k}{m}}[/tex]
[tex]\displaystyle v=\sqrt{\frac{2*4,116}{4,200}}[/tex]
[tex]\displaystyle v=\sqrt{1.96}[/tex]
v = 1.4 m/s
The speed of the lift is 1.4 m/s
Which two life functions of animals help maintain the water cycle by recycling water back into the environment?
Answer:
Respiration and excretion
Explanation:
Respiration. When animals breathe, their lungs release water vapour to the atmosphere.
Animals excrete water by respiration and by passing urine.
Help, please! Thank you for your kind gesture
Answer:
The last option.
Explanation:
Since you are going down, the gravitational potential energy would go down too. Thus, the gravitational potential energy decreases.
Since the gravitational potential energy is converted to kinetic energy when you move down, there is an increase in kinetic energy.
Answer:
The fourth option
Explanation:
Henry designs an experiment to find out why plants without flowers tend to be wind-pollinated and not animal-pollinated. He takes samples from a variety of plants and studies them in the field. He finds that the evidence supports his hypothesis. Which of these was the hypothesis Henry was testing? Choose the correct answer. Nonflowering plants make less pollen than flowering plants. Nonflowering plants lack the structures to attract animal pollinators. Nonflowering plants grow close to the ground and capture fewer pollinators. Nonflowering plants grow close to the ground because they have no pollen grains.
Answer:
option 2
Explanation:
you are very welcom
Help Please! 5 questions for 25 points? seems fair? Thank you!
Answer:
1. where the skater turns and goes back in the opposite direction- point w
2. gravitational force of the object
3. point a
4. the bar representing sphere 4 should be twice as tall as the bar representing sphere 2
5. B; its mass is smaller (?)
yolo
Answer:
ABCDEFGHIJKLMNOPQRSTUVWXYZ
Explanation:
If Minnie the Mouse starts moving at 2m/s and increases her velocity to 4m/s because she is being chased, what is heracceleration if the time is 2 seconds?
Answer:
1m/s²
Explanation:
Given parameters:
Initial velocity = 2m/s
Final velocity = 4m/s
Time of chase = 2s
Unknown:
Acceleration = ?
Solution:
Acceleration is the rate of change of velocity with time;
A = [tex]\frac{v - u }{t}[/tex]
A is the acceleration
v is the final velocity
u is the initial velocity
t is the time taken
A = [tex]\frac{4 - 2}{2}[/tex] = 1m/s²
ANSWER QUICK 30 POINTS
What force controls the movement of the planets around the sun, holds together stars grouped in galaxies, and galaxies grouped in clusters? Thoroughly explain your answer, making sure to include an example and describe how this force keeps planets in orbit. Make sure to write at least 3-5 sentences and proper conventions (spelling, grammar, punctuation, etc.) to respond. Put all answers in your own words
Answer:
Gravity controls the movement of the planets around the sun, holds together stars grouped in galaxies, and galaxies grouped in clusters. The Universal Law of Gravitation depends on two things. First it depends on mass of each object and the second factor is the distance between two objects. If the mass of one object is Larger, the gravitational pull towards it will be larger and the smaller distance, the larger the gravitational pull will be between the objects. Therefore the Larger planets have more moon and the inner planets have less.
Explanation:
A professional golfer walks at an at an average rate of 4.20 meters per second on the golf course. The amount of time required for her to walk from the tee to the green 622 meters away is
Answer:
T try d add b CD c
Explanation:
Cdgffd
A ball is thrown with 50J of kinetic energy, it hits a target which moves with 30J of kinetic energy, how much energy goes to the thermal store of the surroundings?
Answer:
The energy that will go will for thermal store of the surroundings is 20 J.
Explanation:
Given;
kinetic of the thrown ball, K.E₁ = 50 J
kinetic energy used to move the target, K.E₂ = 30 J
The excess energy that will go will for thermal store of the surroundings;
ΔK.E = K.E₁ - K.E₂
ΔK.E = 50J - 30J
ΔK.E = 20 J
Therefore, the energy that will go will for thermal store of the surroundings is 20 J.
which unit would be most
suitable for its scale?
Answer:
down below
Explanation:
for a scale, kg is used, as well as grams
for force, newtons is used
please answerrr asapp tyty Laura goes for cycle from her house to the post office 4km away how long did it take for Laura to reach the post office
Answer:
See the answer below
Explanation:
The time Laura took to reach the post office would depend on the speed of cycling.
We know that;
speed = [tex]\frac{distance}{time}[/tex]
hence,
time = [tex]\frac{distance}{speed}[/tex]
Since the distance from Laura's house to the post office is 4 km, the equation becomes;
time = [tex]\frac{4}{speed}[/tex]
Just ensure that the speed is in km per hour, minute, or seconds in order to obtain the time in hours, minutes, or seconds respectively.