# 1)A wooden block of mass m = 4 kg starts from rest on an inclined

```PHYS 221 SI Worksheet
1. Does pushing a block up a ramp at a constant speed require any force? Is any work
being done? (Hint: draw a free body diagram)
2. You’ve got a spring (k = 188N/m) and a block (m = 2 kg) going up a frictionless, 6-mhigh ramp. What is the minimum distance you must push the mass into the spring, so that
it reaches the top of the ramp? (Hint: what is the formula for energy of a spring?)
3. You are making a potato gun for a physics project*. One gun has a muzzle velocity of
110 m/s with a 3kg potato, and you decide against using explosives, but you want to
achieve the same velocity using a spring instead. If the spring you have has k = 8083
N/m, your barrel must be at least how long? (Hint: Think about the kinetic energy of a
spring, and the kinetic energy of the potato in the gun.)
*
SI in no way condones the construction or use of potato guns regardless of educational application.
*
SI in no way condones the construction or use of potato guns regardless of educational application.
```