Chapter 9: Q.7 (page 227)
A 20 g particle is moving to the left at 30 m/s. A force on the particle causes it to move the the right at 30 m/s. How much work is done by the force?
Net work done is Zero
Over 30 million students worldwide already upgrade their learning with Vaia!
All the tools & learning materials you need for study success - in one app.
Get started for free
A gardener pushes a lawnmower whose handle is tilted up above horizontal. The lawnmowerโs coefficient of rolling friction is . How much power does the gardener have to supply to push the lawnmower at a constant speed of ? Assume his push is parallel to the handle.
A horizontal rope with 15 N tension drags a 25 kg box 2.0 m to the left across a horizontal surface. How much work is done by
(a) tension and (b) gravity?
You throw a g coin straight down at m/s from a -m-high bridge.
a. How much work does gravity do as the coin falls to the water below? b. What is the speed of the coin just as it hits the water?
A ice skater is gliding along the ice, heading due north at . The ice has a small coefficient of static friction, to prevent the skater from slipping sideways, but . Suddenly, a wind from the northeast exerts a force of on the skater.
a. Use work and energy to find the skaterโs speed after gliding in this wind.
b. What is the minimum value of that allows her to continue moving straight north?
A horizontal rope with 15 N tension drags a 25 kg box 2.0 m to the left across a horizontal surface. How much work is done by
(a) tension and (b) gravity?
What do you think about this solution?
We value your feedback to improve our textbook solutions.
