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## Homework Statement

Hey guys I have two questions. The first one i'm not sure, while the second one, I have some idea but don't know how to proceed with answering the question.

**1.**

*A rapidly spinning flywheel has been suggested as an energy storage mechanism for cars. Let's consider a*

**300kg**uniform disk flywheel of diameter of**0.5m**spinning at**100 rotations per second**. Find the energy stored in the spinning flywheel. How higha hill could the**1000kg car**(including the flywheel) climb with this energy?**2.**Calculate the force on a

**1kg**chunk of metal near the edge of the disk.

## Homework Equations

**ω=2∏/T**

**E**

_{rot}=0.5Iω^{2}=0.25MR^{2}ω^{2}**E**

_{rot}=E_{p}## The Attempt at a Solution

**1.**

**ω=2∏*100/1=628rads**

^{-1}The total mass of the car is

**1000kg**which includes the flywheels. In total there are 4 flywheels on the car. So the mass of the car is distributed among the 4 wheels.

**M=1000/4=250kg (per wheel)**

Using the third equation,

**E**

_{rot}=0.25*250*0.25^{2}*628^{2}=1540562.5JThis is the energy for one wheel. Therefore, the total energy of the 4 wheel is

**4*1540562.5=6162250J**.

Using conservation of energy (last equation)

**6162250=250*9.8*h**.

Solving for h:

**h=6162250/(250*9.8)=2515m**

**2.**

For this question, I know that I have to find the tangential force, but, how would i start? Is the tangential force a component of centripetal force???

Many thanks :D