Download Applying Newton`s Laws Homework I

Applying Newton’s Laws – I
1. An elephant is pulling a log through the jungle, one end of a rope being tied to the
elephant and the other end being tied to the log. The rope makes an angle of 30o
with the horizontal and is under tension of 4,000 N. (a) What is the horizontal
component of the force? (b) What is the vertical component of the force?
2. Paul is rolling the lawn. The force he applies to the lawn roller handle performs
two functions. It helps to hold the roller on the ground so it doesn’t slip, and it
pushes the lawn roller forward at a constant velocity. Paul is pushing with a force
of 250 N at a direction of 45o into the ground. The lawn roller weighs 100 N. (a)
What is the horizontal force making the lawn roller go forward? (b) What is the
total vertical force holding the roller against the ground?
3. Two men are carrying a trunk. They each support half the weight, but they also
pull sideward against each other to hold the trunk away from their legs. Each man
pulls with a force of 200 N at a direction 12o from the vertical. (a) How heavy is
the trunk? (b) How hard do the two men pull against each other?
4. A concrete bucket on low friction wheels is being held stationary on a ramp. The
cable holding the bucket is parallel to the ramp. The force exerted by the ramp on
the wheels is perpendicular to the ramp. The weight of the bucket and contents is
1,000 kg and the ramp makes an angle of 25o to the horizontal. (a) What is the
force with which the ramp pushes on the bucket? (b) What is the tension in the
cable?