Question

In: Physics

A child on a sled starts from rest at the top of a 20.0° slope. 1)...

A child on a sled starts from rest at the top of a 20.0° slope.

1)

Assuming that there are no forces resisting the sled’s motion, how long will the child take to reach the bottom of the slope, 250 m from the top? (Express your answer to two significant figures.)

Expert Solution

Answer:-

The child take 12.2 seconds to reach the bottom of the slope.

Explanation:-

Given:

Angle at the horizontal :
Distance from top to the bottom of the slope :
Acceleration due to gravity :

From the free body diagram, the force on the sled along the slope is given by,

Where, F is,

Therefore,

Where,

: is the mass of the sled
: is the acceleration of the sled

Now, from kinematic equation we have,

Where, u is the initial velocity of the sled. Since the sled starts from the rest, the initial velocity will be zero, i.e.

By plugging the value from equation (1) in above expression,

This is the time required for child to reach the bottom of the slope.

genius_generous answered 1 year ago

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