3) A 10kg object rests on a frictionless surface when it is struck by a 300N force. At what rate will it accelerate?

3m/s/s
30m/s/s
0.3m/s/s
300m/s/s

Answer:

positive- downward

negative- upward

Explanation:

A vector is a quantity described by a magnitude and a direction.

The algebraic sign, positive (+) and negative (-) are used to designate the distance and velocity vectors for an object in free fall where positive represents downward  and negative represents an upward movement of the object.

Hence, the correct answer is "positive- downward  and negative- upward".

Answer:98

Explanation:hope this helps!

Answer:

a). a = F/m

Explanation:

Formula is F=ma

Answer:

1.736m/s²

Explanation:

According to Newton's second law;

[tex]\sum F_x = ma_x\\[/tex]

[tex]Fm - Ff = ma_x\\[/tex] where;

Fm is the moving force = 70.0N

Ff is the frictional force acting on the body

[tex]Ff = \mu R\\Ff = \mu mg\\[/tex]

[tex]\mu[/tex] is the coefficient of friction

m is the mass of the object

g is the acceleration due to gravity

a is the acceleration/deceleration

The equation becomes;

[tex]Fm - Ff = ma_x\\Fm - \mu mg = ma\\[/tex]

Substitute the given parameters

[tex]Fm - \mu mg = ma\\70 - 0.18(20)(9.8) = 20a\\70-35.28 = 20a\\34.72 = 20a\\a = \frac{34.72}{20}\\a = 1.736m/s^2\\[/tex]

Hence the deceleration rate of the wagon as it is caught is 1.736m/s²

Answer:

HOPE IT HELPS.....

Explanation:

The legal standard for drunkenness across the United States ranges from 0.10 to 0.08. If a person's BAC measures 0.08, it means that there are 0.08 grams (i.e., 80 mg) of alcohol per 100 ml of blood. The American Medical Association says that a person can become impaired when the blood alcohol level hits 0.05.

Answer: 0.08

Driving While Intoxicated or Impaired is Illegal

Under Michigan law, it is illegal to drive: While intoxicated, or impaired, by alcohol, controlled substance, or other intoxicating substance. With a bodily alcohol content of 0.08 or more. (This crime is one of the driving while intoxicated offenses.)

Hope this helps... Stay safe and have a Merry Christmas!!!!!!!! :D

Answer:

a) [tex]H_{in}=39.34 kJ[/tex]

b) Efficiency=76.77%

Explanation:

a)

In order to solve this problem, we can use the following formula:

[tex]H_{in}=H_{out}+W[/tex]

the problem provides us with all the necessary information so we can directly use the formula:

[tex]H_{in}=9.14kJ+30.2kJ[/tex]

[tex]H_{in}=39.34 kJ[/tex]

b) In order to find the efficiency, we can use the following formula:

[tex]Efficiency=\frac{W}{H_{in}}*100\%[/tex]

so we get:

[tex]Efficiency=\frac{30.2kJ}{39.34kJ}*100\%[/tex]

Efficiency=76.77%

Answer:

chemical symbol: Th

atomic number:90

protrons :90

neutrons:142

group#:4

period#: 9

Explanation:

you take the atomic weight (232.038)and subtract the atomic number to get (90) which is your neutrons

Answer:

in a spontaneous process, the entropy of the universe increases.

Explanation:

Entropy is a measure of of the degree of  randomness or disorderliness in a system.

The second law of thermodynamics can be stated as follows; "in any spontaneous process, the entropy of the universe increases."  

The universe here refers to the system's disorder and the disorder of the surroundings.  Therefore, a spontaneous process can occur, in which the entropy of the system decreases, only if the entropy increases in the surroundings.

For instance, when ice freezes, the entropy of liquid water decreases, that is, the entropy of the system decreases. However, heat is given off to the surroundings and the entropy of the surroundings increases. This is an obvious expression of this law.

Ans    4 more to be exact

Explanation:

Given values are:

Spring constant,

and,

The force will be:

→ [tex]F = kx[/tex]

By substituting the values, we get

      [tex]= 40\times 10[/tex]

      [tex]= 400 \ N[/tex]

Thus the above answer is right.

Learn more about spring constant here:

https://brainly.com/question/15277652

Answer:

i don't know the correct answer

but this is what i found on web

Explanation:

Changes of state are physical changes in matter. They are reversible changes that do not change matter's chemical makeup or chemical properties. Processes involved in changes of state include melting, freezing, sublimation, deposition, condensation, and evaporation. Energy is always involved in changes of state.

Answer:

The answer is 493.05kJ

Explanation:

given

mass m= 3kg

t1=  10°C

t2= 60°C

Specific heat capacity of ham =3287 cal/kgºC

Required,

The quantity of heat, Q

Step two:

the formula is

Q= mcΔT

substitute

Q= 3*3287(60-10)

Q=9861*50

Q=493050 J

Q= 493.05kJ

Answer:

The drill's angular displacement during that time interval is 24.17 rad.

Explanation:

Given;

initial angular velocity of the electric drill, [tex]\omega _i[/tex] = 5.21 rad/s

angular acceleration of the electric drill, α = 0.311 rad/s²

time of motion of the electric drill, t = 4.13 s

The angular displacement of the electric drill at the given time interval is calculated as;

[tex]\theta = \omega _i t \ + \ \frac{1}{2}\alpha t^2\\\\\theta = (5.21 \ \times \ 4.13) \ + \ \frac{1}{2}(0.311)(4.13)^2\\\\\theta = (21.5173 ) \ + \ (2.6524)\\\\\theta =24.17 \ rad[/tex]

Therefore, the drill's angular displacement during that time interval is 24.17 rad.

Answer:

options B,C,D are true

Explanation:

Answer:

D i think

Explanation:

Heavier objects (objects with more mass) are more difficult to move and stop.

Answer:

Increasing the mass of the object (option D in the list of answers)

Explanation:

Recall that F = m x a

therefore, if the mass increases, the force increases

Answer:

B. The magnet has magnetized the right side of the block.

Explanation:

a pe x

Answer:

The distance is 0.96m

Explanation:

Given

m1= 900kg

m2= 1600kg

Force F= 0.0001nN

G=6.67430*10^-11 Nm^2/kg^2

Required

The distance r

Step two:

the formula for the force is given as

F = Gm1m2/r2

make r subject of the formula

[tex]r= \sqrt{\frac{Gm1m2}{F} }[/tex]

[tex]r= \sqrt{\frac{6.67430*10^-11*900*1600}{0.0001} }\\\\r= 0.00009610992/0.0001`}\\\\r= 0.96m[/tex]

Answer:

The distance is 0.96m

Explanation:

Given

m1= 900kg

m2= 1600kg

Force F= 0.0001nN

G=6.67430*10^-11 Nm^2/kg^2

Required:

The distance r

Step two:

the formula for the force is given as

F = Gm1m2/r2

make r subject of the formula

[tex]r= \sqrt{\frac{Gm1m2}{F} }[/tex]

[tex]r= \sqrt{\frac{6.67430*10^-11*900*1600}{0.0001} }\\\\r= 0.00009610992/0.0001`}\\\\r= 0.96m[/tex]

Answer:

The distance between the compact car and pickup truck is 0.96048 m

Explanation:

The gravitational force is directly proportional to the product of the masses of the interacting object, it is also inversely proportional to the square of the distance between them.  This is shown in equation 1;

[tex]F =G \frac{m_{1} X m_{2} }{d^{2} }[/tex]............ 1

Where F is the gravitational force = 0.0001 N

G is the gravitational constant = 6.673 x [tex]10^{-11} Nm^{2} kg^{-2}[/tex]

[tex]m_{1}[/tex]  is the mass of the compact car = 900kg

[tex]m_{2}[/tex] is the mass of the pickup truck = 1600kg

d is the distance and its unknown ?

Let us make d the subject formula in equation 1

[tex]d = \sqrt{G\frac{m_{1} m_{2} }{F } }[/tex] .... 2

Substituting into equation 2 we have

[tex]d = \sqrt{\frac{6.673x10^{-11} x 900 x 1600}{0.0001N} }[/tex]

d = 0.96048m

Therefore the distance between the compact car and pickup truck is 0.96048 m

Answer:

The fundamental frequency is  [tex]f_1 =128 \ Hz[/tex]

Explanation:

From the question we are told that

   The frequency of one harmonics is  [tex]f_x= 448 \ Hz[/tex]

    The next higher harmonic is  [tex]f_z = 576 \ Hz[/tex]

Generally the frequency of an air column open at both ends is mathematically represented as

              [tex]f_n = \frac{nv }{ 2 L }[/tex]

Here n  is the order of the harmonics (frequency)

        v is the velocity of the sound

        L  is the length of the column

So for one harmonics we have that

        [tex]f_k = \frac{n v }{2L}[/tex]

Then for the next higher harmonics

       [tex]f_x = \frac{n+1 ) v}{2 L }[/tex]

Generally the difference between these frequencies is mathematically represented as  

       [tex]f_z- f_x = \frac{(n+1 )v}{ 2L} - \frac{(n )v}{ 2L}[/tex]

=>    [tex]576 - 448 = \frac{vn + v - nv }{2L}[/tex]

=>    [tex]\frac{ v }{2L} = 128[/tex]

Generally for fundamental  frequency n =  1

So  

       [tex]f_1 = n * \frac{v}{2L}[/tex]

So

       [tex]f_1 =1 * 128[/tex]

=>    [tex]f_1 =128 \ Hz[/tex]

Answer:

It's C. Moving Waterrrr

Answer:

The half-life is [tex] t_{1/2} = 1.005 h[/tex]

Explanation:

Using the decay equation we have:

[tex]A=A_{0}e^{-\lambda t}[/tex]

Where:

We know the activity decrease by a factor of two in a one hour period (t = 1 h), it means that [tex]A = \frac{A_{0}}{2}[/tex]

[tex]\frac{A_{0}}{2}=A_{0}e^{-\lambda*1 h}[/tex]

[tex]0.5=e^{-\lambda*1 h}[/tex]

Taking the natural logarithm on each side we have:

[tex]ln(0.5)=-\lambda[/tex]

[tex]\lambda=0.69 h^{-1}[/tex]

Now, the relationship between the decay constant λ and the half-life t(1/2) is:

[tex]\lambda = \frac{ln(2)}{t_{1/2}}[/tex]

[tex] t_{1/2} = \frac{ln(2)}{\lambda}[/tex]

[tex] t_{1/2} = \frac{ln(2)}{0.69}[/tex]

[tex] t_{1/2} = 1.005 h[/tex]

I hope it helps you!

Answer:

Decreasing

Hope this helps! :)

Answer:

its D: A frozen lake melts under the sun.

Explanation:

Radiation is the transfer of heat energy through space by electromagnetic radiation. Most of the electromagnetic radiation that comes to the earth from the sun is invisible. Only a small portion comes as visible light. Light is made of waves of different frequencies.

Answer:

The sun is the ultimate source of energy for all food chains. Through the process of photosynthesis, plants use light energy from the sun to make food energy. Energy flows, or is transferred through the system as one organism consumes another.

Answer:

1.898 × 10^27 kg

Explanation:

thats how much it ways

Explanation:

Given parameters:

Mass of Jogger  = 60kg

Time  = 4s

Vertical height  = 4.5m

Unknown:

Jogger's power output  = ?

Energy required  = ?

Solution:

The power output of the jogger is defined as the rate at which work is done.

 Power  = [tex]\frac{force x distance}{time}[/tex]  

Now insert the parameters and solve;

  Work done = Force x distance = mgh

   m is the mass

   g is the acceleration due to gravity = 9.8m/s²

    h is the height

  Work done  = 60 x 9.8 x 4.5  = 2646J

 Power = [tex]\frac{2646}{4}[/tex]   = 661.5W

Energy required;

 The work done here is also the energy required;

 Energy required  = 2646J

The energy required is 2646 J and the jogger's power output 661.5 W.

Given here,

Mass of Jogger  = 60 kg

Time  = 4s

Vertical height  = 4.5 m

The power output of the jogger is defined as the rate of energy tranfer  work is done.

Power  =  W/t

Where,

W- work = mgh = 60 kg  x  9.8 m/s² x 4.5 m = 2646 J

t - time - 4 s

Put the values, we get

Power = 661.5W

To know more about power,

https://brainly.com/question/8288959

Potential energy+Kinetic energy=Total energy

When you release a spring the velocity increases, therefore the kinetic energy increases ke=1/2*mv^2 and the displacement decreases therefore the potential energy decreases pe=1/2*kx^2.

Complete Question

What is the minimum angular velocity (in rpm) for swinging a bucket of water in a vertical circle without spilling any? The distance from the handle to the bottom of the bucket is 35 cm. The student has 70-cm-long arms

Answer:

The value is  [tex]w__{rpm} } = 29.17 \ rpm[/tex]

Explanation:

From the question we are told

    The distance from the handle to the bottom of the bucket is  [tex]d = 35 \ cm = 0.35 \ m[/tex]

      The length of the students arm is  L = 70 cm  = 0.70  m

   Generally the acceleration due to gravity experienced by the bucket of  water is mathematically represented as

       [tex]g = w^2 * r[/tex]

Here is is the radius of the circle which swinging of the bucket makes and this is mathematically represented as

       [tex]r = L + d[/tex]

So

         [tex]g = w^2 * ( L + d )[/tex]

= >     [tex]w = \sqrt{\frac{g }{ L + d } }[/tex]

= >     [tex]w = \sqrt{\frac{ 9.8}{ 0.7 + 0.35} }[/tex]

= >     [tex]w = 3.055 \ rad/s[/tex]

Generally the angular speed in revolution per minute is mathematically represented as

        [tex]w__{rpm} } = \frac{w * 60 }{2 \pi }[/tex]

=>      [tex]w__{rpm} } = \frac{3.055 * 60 }{2 * 3.142 }[/tex]

=>      [tex]w__{rpm} } = 29.17 \ rpm[/tex]

Answer:

Fx = 467.65N

Fy = 270N

Explanation:

Given

Force = 540N

angle of inclination = 40 degree

Horizontal component Fx = Fcos 30

Fx = 540cos30

Fx = 540(0.8660)

Fx = 467.65N

Hence the horizontal component is 467.65N

Vertical component Fy = Fsin 30

Fy = 540sin30

Fy = 540(0.5)

Fy = 270N

Hence the vertical component is 270N

Answer:

t = 66.7 s

Explanation:

Given that,

Speed of a hare, v = 15 m/s

Speed of a turbocharged tortoise, v' = 3 m/s

The hare in a 250 meter race

Let the Hare takes time t. It can be calculated as follows :

[tex]t=\dfrac{250}{15}=16.67\ s[/tex]

Let a turbocharged tortoise takes t'. It can be calulated as follows :

[tex]t'=\dfrac{250}{3}= 83.33\ s[/tex]

To tie the race, required time is given by :

[tex]\Delta t = t'-t\\\\=83.33-16.67\\\\=66.66\ s\\\\\approx 66.7\ s[/tex]

Hence, the correct option is (b) i.e. 66.7 seconds.