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3 years ago

“A horse pulls on a cart. By Newton’s third law of motion, the cart pulls back on

2 answers:

Studentka2010 [4]3 years ago

8 0

In order to see what's going on, let's put them in empty space to get rid of any other influences, and let's also make it a push instead of a pull. / / / The horse pushes on the cart, so it begins accelerating away from him. At the same time, because of the equal opposite reaction thing, the cart pushes back on the horse, so the horse starts accelerating backwards, away from the cart. They both accelerate in opposite directions from where they started. BUT . . . their common center of mass doesn't move, and the sum of their momentums (which are in opposite directions) remains zero.

Slav-nsk [51]3 years ago

4 0

If they are both in space and not on ground, then the above way of thinking is correct. Horse will not be able to accelerate forward.

But here, there are some external forces acting on the horse other than the pull of the cart. That makes the horse accelerate. Cart also gets accelerated.

Horse kicks and pushes the road or ground with his feet backwards. So the ground pushes with an equal force in the forward direction. On the horse, there is a force by the cart, pulling it backwards and a force of friction from the ground and a push forward given by the ground. Pushing forward force by the ground is higher than the sum of others. So horse accelerates.

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Which four equations can be used to solve for acceleration

emmainna [20.7K]

The four equations for acceleration are obtained from the three equations of motion and from second law of motion.

Explanation:

Acceleration is defined as the rate of change of velocity with respect to time. So the change in velocity with respect to time can be determined using the three equations of motions.

So from the first equation of motion, v = u + at , we can determine the value of acceleration if time taken, final and initial velocity is known. The equation can be re-written as $a = \frac{v-u}{t}$

Similarly, from the second equation of motion, s = ut + 1/2 at², we can determine the equation for acceleration as $a = 2*\frac{s-ut}{t^{2} }$

So this is second equation for acceleration.

Then from the third equation of motion, $v^{2}- u^{2} = 2* a *s$

the acceleration equation is determined as $a = \frac{v^{2}-u^{2} }{2s}$

In addition to these three equation, another equation is present to determine the acceleration with respect to force from the Newton's second law of motion. F = Mass × acceleration. From this, acceleration = Force/mass.

So, these are the four equations for acceleration.

8 0

3 years ago

An inductance L, resistance R, and ideal battery of emf are wired in series. A switch in the circuit is closed at time t = 0, at

Kay [80]

Explanation:

After some time t the current does not passing through the circuit

=>so the back emf is zero

=>here the inductor opposes decay of the circuit

- Ldi/dt = Ri

di/dt = - R/Li

di/i = - R/Ldt

now we applying the integration on both sides

log i=-R/Lt+C

here t=0=>i=io

Log io=C

=>Log i=-R/L*t + Log io

logi-Log io=-R/L*t

Log[i/io]=-R/L*t

i/io=e^-Rt/L

i=ioe^-Rt/L

the option D is correct

3 0

3 years ago

Read 2 more answers

gizmo_the_mogwai [7]

Answer:

a) P1=100kpa

V1=6m³

V2=?

P2=50kpa

rearranging mathematically the expression for Boyle's law

V2=(P1V1)/P2=(100×6)/50=12m³

b) same apartment as in (a) but only the value of P2 changes

=> V2=(100×6)/40=15m³

Explanation:

since temperature is not changing we use Boyle's law. mathematically expressed as P1V1=P2V2

4 0

2 years ago

A particular planet has a moment of inertia of 9.74 × 1037 kg ⋅ m2 and a mass of 5.98 × 1024 kg. Based on these values, what is

malfutka [58]

Answer: A) $6.38(10)^{6} m$

Explanation:

The equation for the moment of inertia $I$ of a sphere is:

$I=\frac{2}{5}mr^{2}$ (1)

Where:

$I=9.74(10)^{37}kg m^{2}$ is the moment of inertia of the planet (assumed with the shape of a sphere)

$m=5.98(10)^{24}kg$ is the mass of the planet

$r$ is the radius of the planet

Isolating $r$ from (1):

$r=\sqrt{\frac{5I}{2m}}$ (2)

Solving:

$r=\sqrt{\frac{5(9.74(10)^{37}kg m^{2})}{2(5.98(10)^{24}kg)}}$ (3)

Finally:

$r=6381149.077m \approx 6.38(10)^{6} m$

Therefore, the correct option is A.

4 0

2 years ago

What is 800,000,000 meters in scientific notation

Paladinen [302]

8 x 10^8 = 800,000,000

In Scientific Notation, your goal is to get your the number you're multiplying by 10 (8 in this case) to be between 0 and 10. Therefore, you would NOT have 80 x 10^7 because 80 is not between 0 and 10.

7 0

3 years ago

Read 2 more answers