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Dear Everybody

There is a ball which has mass of 11 grams is thrown straight up with an initial speed of 4 m/s. Assume the air drag is negligible.

a. What is the kinetic energy of the ball (in J) as it leaves the hand? b. How much work is done by the gravitational force during the ball's rise to its zenith? c. What's the change in the gravitational potential energy of the ball during the ball's rise to its zenith? d. If the grav. force is taken zero at the pt. where it leaves your hands, what's the grav. pot. energy when it reaches the max. height? e. If the grav. force is taken zero at the pt. where it leaves your hands, what would the grav. pot. energy when it reaches the max. height? f. What is the max height the ball reaches?

The work:

The known values

mass is 11 grams

The initial velocity is 4m/s

The final velocity is 0

the value of gravity is 9.81m/s*s

a. I need to convert grams to kilograms. 11 grams to .011 kg. Then use kinetic energy which $K=(mv^2)/2$.

the answer is .088J.

There is a ball which has mass of 11 grams is thrown straight up with an initial speed of 4 m/s. Assume the air drag is negligible.

a. What is the kinetic energy of the ball (in J) as it leaves the hand? b. How much work is done by the gravitational force during the ball's rise to its zenith? c. What's the change in the gravitational potential energy of the ball during the ball's rise to its zenith? d. If the grav. force is taken zero at the pt. where it leaves your hands, what's the grav. pot. energy when it reaches the max. height? e. If the grav. force is taken zero at the pt. where it leaves your hands, what would the grav. pot. energy when it reaches the max. height? f. What is the max height the ball reaches?

The work:

The known values

mass is 11 grams

The initial velocity is 4m/s

The final velocity is 0

the value of gravity is 9.81m/s*s

a. I need to convert grams to kilograms. 11 grams to .011 kg. Then use kinetic energy which $K=(mv^2)/2$.

the answer is .088J.

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