Kinetic energy after falling to 100m

AI Thread Summary
A 250 g object is dropped from a height of 150 m, and the kinetic energy after falling to 100 m is being calculated. The kinematics equation V2^2 = V1^2 + 2ad is applied to find the final velocity, followed by the kinetic energy formula Ek = 1/2 mv^2. The initial calculation yielded 120 J, but there is uncertainty about its accuracy. An alternative approach suggests calculating the change in gravitational potential energy and equating it to kinetic energy. This method can also confirm the kinetic energy at the specified height.
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Homework Statement


A 250 g object is dropped from a height of 150 m. What is the kinetic energy after falling to 100m

Homework Equations


V2^2 = V1^2 +2ad
Ek = 1/2 mv^2

The Attempt at a Solution


I used the kinematics equation to find my v2 then I used this to find Ek. I got the answer 120J but I'm not sure if I'm doing this right
 
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Smartgurl said:

Homework Statement


A 250 g object is dropped from a height of 150 m. What is the kinetic energy after falling to 100m

Homework Equations


V2^2 = V1^2 +2ad
Ek = 1/2 mv^2

The Attempt at a Solution


I used the kinematics equation to find my v2 then I used this to find Ek. I got the answer 120J but I'm not sure if I'm doing this right
That solution should work, alternatively you could find the change in the gravitational potential energy and equate that change to the kinetic energy.
 

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