PHYSICS
COLLEGE

Answer:

Answer:

Explanation:

Given

radius of Planet is equal to radius of Earth

Weight of body on Planet

where m=mass of body

Weight of body on earth

acceleration due to gravity is given by

where G=gravitational constant

M=mass of Planet

r=radius of planet

for earth

for planet

substituting these values in and

divide 1 and 2

MIDDLE SCHOOL

Give examples to show that friction is both a friend and a foe.

Explanation:

Wind resistance is a kind of friction we usually try to minimize. It makes our cars and planes run less efficiently. At the same time though, we need friction between our tires and the road to move, as well as friction in our brakes to stop. We wouldn't be able to walk without friction, or start a campfire by rubbing sticks together.

HIGH SCHOOL

Which letter represents the direction of the centripetal force?

I think there should be a picture。

But the direction of the centripetal force is towards the center。

Hope that helps。

But the direction of the centripetal force is towards the center。

Hope that helps。

MIDDLE SCHOOL

Is a cremated flower pot a good conductor? please help.

Answer:

It depends on the size and density but No.

Explanation:

HIGH SCHOOL

a 3.0 kg mass moving to the right at 1.4 m/s collides in a perfectly inelastic collision with a 2.0 kg mass initially at rest. what will the velocity of the combined mass be after the collision? show your work

The velocity of the combined mass after the collision is 0.84 ms-1.

Explanation:

According to law of conservation of momentum, the change in momentum before collision will be equal to the change in momentum of the objects after collision in isolated system.

But as it is perfectly inelastic collision in the present case, the final momentum will be based on the product of total mass of both the object with the velocity with which the collision occurred. This form is attained from the law of conservation of momentum as shown below:

So as law of conservation of momentum,

Here = 3 kg and = 2 kg are the masses of objects 1 and 2, = 1.4 m/s and = 0 are the initial velocities of object 1 and object 2, and are the final velocities of the objects.

So after collision, object 1 get sticked to object 2 and move together with equal velocity = = . Thus the above equation will become,

So the final velocity is

Thus,

= 0.84 ms-1.