[iheartcaffeine]

Please explain the steps in how you got your answers because I'm lost at this point. I need to find the angle on the first problem and the answer is in joules in the 2nd. These are the last 2 problems on my assignment and I cannot solve them.

A 1300 kg car has a maximum power output of 110 hp. How steep a hill can it climb at a constant speed of 110 km/h if the frictional forces add up to 800 N?

Coasting along at 8.20 m/s, a 60.0 kg bicyclist on a 7.70 kg bicycle encounters a small hill. If the speed of the bicyclist is 6.00 m/s at the top of the hill, how much work was done on the bicyclist and her bike?
J

[Chris-infj]

I'll answer the first one:

1. I would use SI units
2. Draw a picture
3. Put all the forces acting on the car,

Namely the driving force (in which direction is it acting?)
The frictional forces (in which direction are those acting?)
And then think - if the car is on an inclined plane, how are you going to resolve the weight and in which two perpendicular directions? Which component matters? That's where your angle comes in...

4. How is driving force related to the Power given? Find that formula.
5. etc.

[ebaines]

As for the second problem...

Consider the change in kinetic energy of the rider & bike. This change in KE is equal to the work done in gaining potential energy climbing the hill.

[Chris-infj]

To the OP, where are you at solving this prob?