All categories

2 years ago

the moon revolves around the earth in a nearly circular orbit kept by gravitational force exerted by the earth work done will be

Physics

1 answer:

rodikova [14]2 years ago

3 0

Answer:

Zero because the applied force is perpendicular to the motion of the object.

No work is done on an object moving is a circular path about a central attractive force.

Any work done in such a case would result in a change in the orbit.

You might be interested in

What is the approximate value of the gravitational force between a 73 kg astronaut and a 7.1×104 kg spacecraft when they're 89 m

Luden [163]

Answer:

$F = 4.3671 * 10^{-8}\ Newtons$

Explanation:

The gravitational force between two corpses is given by the following equation:

$F = GMm/d^2$

Where F is the force, G is the gravitational constant

( $G = 6.67408*10^{-11}\ m^3kg^{-1}s^{-2}$ ), M and m are the masses of the corpses and d is the distance between them.

So we have that:

$F = 6.67408*10^{-11} * 7.1*10^4 * 73/89^2$

$F = 4.3671 * 10^{-8}\ Newtons$

5 0

3 years ago

According to Wien's Law, how many times hotter is an object whose blackbody emission spectrum peaks in the blue, at a wave lengt

scZoUnD [109]

Answer:1.55 times

Explanation:

Given

First wavelength $(\lambda _1)=450 nm$

Second wavelength $(\lambda _2)=700 nm$

According wien's diplacement law

$\lambda T=constant$

where $\lambda =wavelength$

T=Temperature

Let $T_1 and T_2$ be the temperatures corresponding to $\lambda _1 & \lambda _2$ respectively.

$\lambda _1\times T_1=\lambda _2\times T_2$

$\frac{T_1}{T_2}=\frac{\lambda _2}{\lambda _1}$

$\frac{T_1}{T_2}=\frac{700}{450}=1.55$

Thus object with $\lambda 450 nm$ is 1.55 times hotter than object with wavelength $\lambda =700 nm$

8 0

3 years ago

When the pendulum bob reaches the mean position, the net force acting on it is zero. Why then does it swing past the mean positi

ryzh [129]

Answer:

<u>The pendulum bob swing past the mean position because:</u>

When a pendulum's bob is accelerating at its extreme position its velocity is zero. Due to the restoring toque the bob starts to accelerates towards its mean postion. The maximum acceleration of the pendulum's bob is $-w^{2} A$ and the the acceleration decreases as $-w^{2} x$ towards the mean position.

The acceleration at the mean position becomes zero but the velocity remains maximum. Hence the bob continues to move and does not stops.Thus it can summarised as the force decreases ,acceleration decreases and velocity increases at slow rate.

6 0

2 years ago

A 10cm long wire is pulled along a U-shaped conducting rail in a perpendicular magnetic field. The total resistance of the wire

soldi70 [24.7K]

Answer:

a) $v=4.0m/s$