# Skill Set 05.1

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### 1. What is the period of a merry-go-round with a radius of 1.75 m if the centripetal acceleration at this point is 7.2 m/s/s? (3.1 s)

The formula for this problem is:

After you plug the numbers in, it's pretty straight forward to solve for the time (T)

Take the square root of both sides..

2. What is the velocity of a 1350 kg car going around a 213 m radius corner if the frictional force is 9830 N? (39.4 m/s)

Jus plug in your numbers into tha formula

Multiply by 213

Divide by 1350

Square root it baby

3. Tycho twirls a 2.7 kg hammer at 6.2 m/s around a 5.6 m radius circle. What force in what direction must he exert on the hammer at the top and at the bottom? (8.0 N up, and 45 N up)

Forrmmmuullaaas:

Find tha acceleration please

Find tha force please

Plug er in there

^(accel = negative cuz it's at the top)^

4. At what distance from the center of a 4.59 x 10^{24} kg planet is the gravitational force on a 15.0 kg object equal to 60.0 N? (8.75x10^{6 }m)

Use:

Which equals..

Plug your numerical information in

Do yo thing

5. Your 12,500 kg spaceship is orbiting 1.16x10^{7} m from the center of a planet every 17,500 s. What is the mass of the planet? (3.02x10^{24} kg)

Formula is

Plug your junk in