Question

A marble rolls off a tabletop 0.70 m high and hits the floor at a point 3.5 m away from the table's edge in the horizontal direction.

(a)

How long (in s) is the marble in the air?

__________________________________________ s

(b)

What is the speed of the marble (in m/s) when it leaves the table's edge?

__________________________________________ m/s

(c)

What is its speed (in m/s) when it hits the floor?

__________________________________________m/s

Answer 1

The initial height of the marble,

The horizontal distance covered by the marble,

The marble rolls off the table in a horizontal direction, so initial vertical velocity,

(a) How long is the marble in the air?

Consider the vertical motion of the marble

Use formula

(a) ANSWER:

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(b) What is the speed of the marble when it leaves the table's edge?

The marble rolls off the table in a horizontal direction, so initial vertical velocity,

Consider the horizontal motion of the marble

There is no acceleration in the horizontal direction, so horizontal velocity remains constant.

Horizontal velocity = Horizontal distance/time

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Initial velocity,

(b) ANSWER:

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(c) What is its speed when it hits the floor?

Consider the horizontal motion of the marble

There is no acceleration in the horizontal direction, so horizontal velocity remains constant.

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Consider the vertical motion of the marble

Use formula

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Final velocity,

(c) ANSWER:

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