Need help with potential energy, kinetic energy ect.

[Justinfrank]

I have home work that I cannot understand, it relates to kinetic energy, and energy potential I cannot find the formula to use to solve it

Heres some of the questions

1.An elastic band is stretched a distance of 15.0cm by a force of 10.0N

A.How much potential energy is stored in the elastic.- I don't understand how to find that out.

2. A 1.00 g object is placed on the elastic, and the elastic is released in a vertical direction. How much energy was transferred to the object by the elastic? Can't figure out how to solve.

A.What was the speed of the object as it leaves the elastic? Don't know the formula

B.How high will the object rise (assume no friction)- Don't know the formula

Please help me solve these questions as this assignment is due tommorow.

And sorry I couldn't show any work I've done, because I cannot figure out where to start with these
questions.

 

[supratim1]

hello Justin, welcome to PF!

for no. 1, work done = potential energy stored. so work done is Force x distance (use SI units)

 

[supratim1]

in no. 2, energy stored in elastic is transferred to object, so it is same value.

3. formula for kinetic energy is 1/2 (mv^2). i suggest you first go through the theory and learn the formulas before solving problems.

 

[supratim1]

use equations of motion for last one. using it you will have

h = v^2/(2g)