Okay, hun. Velocity is a vector quantity that measures displacement over a period of time. Velocity = Speed/Time (v=s/t). Hope this helped you. I took physics over 4 years ago. I'm more of a biology/chemistry person. (I major in those)
define density with a suitable formula
Answer:
ratio between m/v
or d= m/v
m= mass
v= volume
Occupants of cars hit from behind, even at low speed, often suffer serious neck injury from whiplash. During a low‑spee rear‑end collision, a person's head suddenly pivots about the base of the neck through a 50∘ angle, a motion that lasts 220 ms.The distance from the base of the neck to the center of the head is typically about 20 cm, and the head normally comprises about 6.0% of body weight.Model the motion of the head as having a uniform speed over the course of its pivot. Compute answers to two significant figures.1. What is the acceleration ????centacent of the head during the collision?2. What force ????F does the neck exert on the head of a 65 kg65 kg person in the collision? Neglect the force of gravity on the head, and report the answer in units of both newtons and pounds.3. Would headrests mounted to the backs of the car seats help protect against whiplash? Why or why not?a. Yes. A headrest applies an upward force on the head, along the direction of the neck, that cancels the downward force applied by the neck.b. Yes. A headrest ensures that both the head and the body experience the same forward force at roughly the same time.c. No. A headrest applies a mostly horizontal force to the head, so does not affect the mostly vertical force applied by the neck during whiplash.d. No. A headrest reduces the angle traversed by the head, not the speed of the head relative to the body, thus it does not affect the force that the neck applies to the head.
Answer:
a) a= 19 m/s2, b ) F = F = 38 N
c) the correct one is B
Explanation:
1) To solve this exercise, let's use the concept of torque, let's start by looking for the mass of the mass of the head, which is 65 of 65 kg
m= 0.06 65 = 3.9 kg
torque is defined
τ = F x R
the bold indicate vectors
τ = F R sin θ
the force is the weight of the head and the distance R = 0.20 m
τ = mg R sin θ
τ = 3.9 9.8 0.2 sin 50
τ = 5.86 N m
Newton's second law expression for rotational motion is
τ = I α
In general, the head is approximated by a sphere, so the moment of foolishness with respect to the base of the neck (turning point) using the parallel axis theorem is
I = I_sphere + m d²
Neck height data is not indicated, so we will assume that it is zero (d = 0)
I = 2/5 m R²
angular and linear acceleration are related
a = α R
α = a / R
let's replace
τ = 2/5 mR² (a / R)
a = 5/2 τ / mR
let's calculate
a = 5/2 5.86 / (3.9 0.2)
a = 18.8 m / s²
a= 19 m/s²
2) as the neck and the head are related, the forces are action and reaction, therefore the neck force is
F = m g
F = 3.9 9.8 = 38.2 N
F = 38 N
3) He asks us about the efficiency of the headrest, after reviewing the different alternatives, the correct one is B
Yes. A headrest ensures that both the head and the body experience the same forward force at approximately the same time.
The airport has a new plane that can go from 0 miles per hour to 100 miles per hour in 10 seconds. What is being described about the new plane?
a. acceleration
b. speed
c. velocity
d. magnitude
Answer:
acceleration
Explanation: how fast something can get to a certain speed
A proposed space station includes living quarters in a circular ring 58.0 m in diameter. At what angular speed should the ring rotate so the occupants feel that they have the same weight as they do on Earth
Answer:
The angular speed [tex]w = 0.5813 \ rad/s[/tex]
Explanation:
From the question we are told that
The diameter is d = 58.0 m
Generally for the occupants feel that they have the same weight as they do on Earth then the centripetal acceleration of the circular ring must be equal to the acceleration due to gravity this can be mathematically represented as
[tex]a_c = g[/tex]
Here [tex]a_c[/tex] is the centripetal acceleration which is mathematically represented as
[tex]a_c = w^2 * r[/tex]
Here r is the radius of the circular ring
=> [tex]w^2 * r = g[/tex]
=> [tex]w = \sqrt{\frac{g}{r} }[/tex]
=> [tex]w = \sqrt{\frac{9.8}{ \frac{d}{2} } }[/tex]
=> [tex]w = \sqrt{\frac{9.8}{ \frac{58.0 }{2} } }[/tex]
=> [tex]w = 0.5813 \ rad/s[/tex]
If an object has zero acceleration, does it have to have zero velocity?
Answer:
Yes, the velocity would also be zero.
Explanation:
Acceleration is the change in velocity over time, therefore, there has to be a change in velocity for something to accelerate. which means without acceleration, the object has no velocity.
2. True or false?
Forensic entomology uses the study of insects to help criminal investigations.
how does 'g' at a point vary with the distance from the centre of earth?
Answer:
No gravity
Explanation:
because their is not gravity on earth and also close to the sun but not as close as mecury
PEOPLE PLEASE HELP ASAP!!!-How does Force effect acceleration?
Answer:
If the force is higher then the resitance o fht eobject then force will make object accelerate.
Explanation:
Does that make sense. If you need something else as an answer tell me in the comments and please mark with a heart and brainliest. If you don't mind
We know:
Force =Mass×Accerlation
[tex]∴Accerlation = \dfrac{force}{mass} [/tex]
So by seeing this formula we came to know that accerlation is directly proportional to force and inversely proportional to mass.
So by increase of force acceleration also increases.
I will give you branilest!
A race car exerts 18,344 N while the car travels at an acceleration of 92.54 m/s2. What is the mass of the car? (Use the formula m=F/a)
Answer:
The answer is 198.23 kg
Explanation:
To find the mass of an object given it's mass and acceleration we use the formula
where
m is the mass
F is the force
a is the acceleration
From the question
a = 92.54 m/s²
F = 18,344 N
We have
We have the final answer as
198.23 kg
Answer:
198.22
Explanation:
using m=f/a you divide the force by the acceleration to get the mass (18344 / 92.54) = 198.22
what is the acceleration of a cat who starts from rest and moves 11.5 m in 2.8 s?
Answer:
The acceleration is 4
Explanation:
use the formula v= change in position/change in time for vecter quantity's which will be in word problems that say acceleration or velocity.
shannon dropped his ICP textbook. how fast was it going after 3 seconds? how far did it fall? please guys help mee quickly pleaseeee
¡Hola!
For this problem, first, lets recabe information:
v = 0 m/s
t = 3 s
g = 9,82 m/s²
v' = ?
d = ?
First, for calculate the final velocity:
v' = v + g * t
v' = 0 m/s + 9,82 m/s² * 3 s
v' = 29,46 m/s [tex]\leftarrow \boxed{\text{Velocity} }[/tex]
Now, for calculate how far did it fall:
d = v * t + g * t^2 / 2
Like v = 0 m/s, we can simplificate equation:
d = g * t^2 / 2
d = 9,82 m/s² * (3 s)^2 / 2
d = 9,82 m/s² * 9 s² / 2
d = 88,38 m / 2
d = 44.19 m [tex]\leftarrow \boxed{\text{Distance} }[/tex]
¡Buena suerte!
a tractor with 2000 kg of mass pulls a plow equal to 80.0 kg, exerting a 200 N force on it. The tractor and plow set moves horizontally to the right with an acceleration of 0.500 m / s2. The resistance force that the soil exerts on the plow has a modulus, in Newton, equal to?
Answer:
The resistance force that the soil exerts on the plough is 160 Newtons.
Explanation:
Fr = m.a
Fr = 80. 0,5
Fr = 40 N
Ft - F = Fr
200 - F = 40
F = 200 - 40
F = 160 Newtons
You are traveling through the forest and encounter an ancient well. You want to know how deep the well is. If you drop a coin and hear it hit the bottom of the well in 3 seconds, how deep is the well?
Determine the acceleration that an unbalanced force of 28 N gives to a 6.8 kg mass.
Answer:
4.12 m/s^2
Explanation:
unbalanced force means the presence of resultant force (net force)
[tex]net \: force \: = mass \times accleration[/tex]
f = 28N
m = 6.8kg
a = ?
? = 28/6.8
= 4.1176...
approximately = 4.12 m/s^2
What is the freezing point (in degrees Celcius) of 4.62 kg of water if it contains 236.5 g of C a B r 2
Answer:
The new freezing point of water is -0.476°C.
Explanation:
Given that,
Mass of water = 4.62 kg
Mass of CaBr₂ = 236.5 g
We need to calculate the molality of solution
Using formula of molality
[tex]m=\dfrac{mass\ of\ CaBr_{2}}{molar\ mass\ of\ CaBr_{2}\times mass\ of\ water}[/tex]
Put the value into the formula
[tex]m=\dfrac{236.5}{200\times4.62}[/tex]
[tex]m=0.256\ mol/kg[/tex]
[tex]m=0.256\ m[/tex]
We need to calculate the depression in freezing point of water
Using formula of freezing point
[tex]\Delta T=m\times k[/tex]
Where, k = depression constant
m = molality of solution
Put the value into the formula
[tex]\Delta T=0.256\times1.86[/tex]
[tex]\Delta T=0.476^{\circ}C[/tex]
We know that,
The standard freezing point of water is 0°C
We need to find the new freezing point of water
Using formula for freezing point of water
Freezing point of 4.62 kg of water = freezing point of water-depression in freezing point of water
[tex]\Delta T'=0-\Delta T[/tex]
Put the value into the formula
[tex]\Delta T'=0-0.476[/tex]
Hence, The new freezing point of water is -0.476°C.
In a car's suspension system, each wheel is connected to a vertical spring; these springs absorb shocks when the car travels on bumpy roads. In one car, each spring has a spring constant of 4.6 × 10⁴ N/m.
If this 1300 kg car is driven at 23 m/s through the bottom of a circular dip in the road that has a radius of 600 m, by how much do these springs compress compared to when the car is driven on a flat road?
Answer:
6.23 mm
Explanation:
The vertical acceleration at the bottom of the dip (in addition to that required to counter gravity) is ...
a = v²/r = (23 m/s)²/(600 m) = 529/600 m/s²
Then the force on the car (in addition to that required to counter gravity) is ...
F = Ma = (1300 kg)(529/600 m/s²) = 1146 1/6 N
The additional force supplied by each of the 4 springs is 1/4 of this, so the additional spring compression is ...
((1146 1/6 N)/4)/(4.6×10^4 N/m) ≈ 0.00623 m = 6.23 mm
The springs are compressed an additional 6.23 mm to provide the required vertical acceleration.
_____
We have to assume that the path followed by the car's center of mass has a radius of 600 m. We're also assuming that the rotational motion of the car about its center of mass does not require any differential force between front and back springs, as it will be at a constant rate for a constant speed through the dip. And, we assume that the mass of the car is evenly among the four springs (often not the case).
Answer:
Explanation:
Given this 1300 kg car is driven at 23 m/s through a circular dip in the road of radius of 600m,
its centrifugal acceleration = speed^2 / radius
= 23^2 / 600
= 0.8817 m/s^2
The centrifugal force in turn = mass * acceleration
= 1300 * 0.8817
= 1146.17 N
This force is absorbed by suspension springs of the four wheels.
Given spring constant of 4.6 x 10^4 N/m and 4 springs total,
the extra compression = Force / number of springs / spring constant
= 1146.17 / 4 / 4.6 x 10^4
= 0.006229 m
= 6.23 mm
Note that this is the extra compression on springs during drive-through of the dip compared to when the car is driven on a flat road. There is a constant compression on springs due to weight of the car which is the same whether the car is driving through a dip or on a flat road.
Can you help me please! Love you
Answer:
I think its B. wait...U love ME?????
List some of the most common injuries that can occur from sports. Please hurry!
are there really dead stars in the sky?
Answer:
Yes
Explanation:
The star would have died over thousands of years ago but the light takes a long time for it to reach us on Earth.
When you bent the plastic ruler, what did you observe in its size?
Answer:
The size will increase.
Explanation:
When you bend a plastic ruler, it's size will increase because it is elastic and will exhibit elastic deformation. When it is been bent, it will continue to stretch until it get to a point where it will not be able to regain it formal shape, it size wound of increase. Therefore when the ruler get to elastic limit and you have bend it to the point it cannot regain it's formal shape back, it will remain bent and if further force is apply on it,it will break.
If the breaking strength of the string is 120 N, what is the minimum angle the string can make with the horizontal
Complete Question
A 940-g rock is whirled in a horizontal circle at the end of a 1.30-m-long string, If the breaking strength of the string is 120 N, what's the minimum angle the string can make with the horizontal?
Answer:
The value is [tex]\theta = 4.41^o[/tex]
Explanation:
From the question we are told that
The mass of the rock is [tex]m_r = 940 \ g = 0.94 \ kg[/tex]
The length of the string is [tex]l = 1.30 \ m[/tex]
The breaking strength(i.e the maximum tension) on the string is [tex]T = 120 \ N[/tex]
Gnerally the vertical component of the tension experienced by the string is mathematically represented as
[tex]T_v = T sin(\theta)[/tex]
Generally this vertical component of tension is equivalent to the weight of the rock
So
[tex]Tsin (\theta) = mg[/tex]
=> [tex]\theta = sin^{-1} [\frac{mg}{ T} ][/tex]
=> [tex]\theta = sin^{-1} [\frac{0.940 *9.8 }{ 120} ][/tex]
=> [tex]\theta = 4.41^o[/tex]
Why is it important to warm up your muscles?
Warming up the muscles increases lactic acid build up
Warming up the muscles increases temperature and flexibility of your muscles Warming up the muscles increases your risk of injury
All of the above
PLEASE HELP
What do safety symbols look like? What do they mean? Provide at least three examples.
Answer: Safety symbols have a triangle shape, usually the colors are red, orange, and yellow. On the symbol of an element there can be a line going across diagonal They can have symbols that have a person slipping to let you know if someones mopping you may slip. Others may have one that has fire that lets you know fire may happen. And last but not least others can have deers on them to let you deers are on the street/road. Hope this helps.
Explanation:
2 physical properties for manganese
A car is traveling with a velocity of 20 M/S and has a weight (mass) of 1000 kg. The car has kinetic energy calculate it
Answer:
200000 joules or 200 kilojoules
Explanation:
Kinetic energy = 1/2m(v^v)
Kinetic energy = 1/2*1000* 20^20
Kinetic energy = 500*400
Kinetic energy = 200000 joules or 200 kilojoules
A 58.72 kg person holding a steel ball stands motionless on a frozen lake.
The person then throws the ball, which propels the person at 1.05 m/s to the
right and the ball 3.75 m/s to the left. If the initial momentum of the system is
zero, what is the mass of the steel ball?
Answer: 16.44 kg
Explanation:
Which could describe the properties of sedimentary rock?
PLASE HELP
DUE TODAY
Answer:
☝ Some of the properties of sedimentary rocks
A train is traveling at a speed of 50km/hr. How.many hours will it take the train to travel 800 km?
Answer:
It would take 16 hours
Explanation:
800 divided by 50 = 16
Brainly pls
Answer: [tex]t[/tex] = 16
Explanation:
Hey there! I will give the following reason, if you have any questions feel free to ask me in the comments below.
Because a train is traveling at a speed of 50 km/hr and a train needs to travel 800 km, you would need to divide the distance by the speed to find the hours.
Formula: [tex]t[/tex] = [tex]\frac{distance}{speed}[/tex]
The distance would be 800, and the speed would be 50.
[tex]t = \frac{800}{50}[/tex]
Simplify.
[tex]t = 16[/tex]
~I hope this helps you! :)~
1/2
I, the student, verify that I have read the lab safety document and will comply with the rules as stated.
Yes
No
Consider a wire of length L =0.30 m that runs north-south on a horizontal surface. There is a current I = 0.50 A flowing north in tie wire. The Earth's magnetic field at this location has a magnitude of 0.50 gauss (or, in SI units. 0.5 x 10^—4 and points north and 38 degrees down from the horizontal, toward the ground. What is the size of the magnetic force on the wire due to the Earth's magnetic field?
Answer:
The size of the magnetic force on the wire due to the Earth's magnetic field is 4.62 × 10⁻⁶ N.
Explanation:
To determine the size of the magnetic force on the wire due to the Earth's magnetic field,
The magnetic force is given by the formula
F = ILB sinθ
Where F is the magnetic force on the wire
I is the electric current in Amperes (A)
L is is the length of wire in meters (m)
B is the magnetic field in Tesla (T)
and θ is the angle between current and magnetic field
From the question,
L = 0.30 m
I = 0.50 A
B = 0.50 gauss = 0.5 × 10⁻⁴ T (NOTE: 1 Gauss = 10⁻⁴ Tesla)
θ = 38°
Now, putting the values into the equation
F = ILB sinθ
F = 0.50 × 0.30 × 0.5 × 10⁻⁴ sin38°
F = 7.5 × 10⁻⁶ (0.61566)
F = 4.62 × 10⁻⁶ N
Hence, the size of the magnetic force on the wire due to the Earth's magnetic field is 4.62 × 10⁻⁶ N.