A police siren sounds different as it comes close to you than when it moves away from you. what term explains how this happens?

a. diffraction

b. the doppler effect

c. rarefaction

d. shockwaves

You must exert a force of 4.5N on a book to slide it across a table. If you do 3.7J of work in the process, how far have you moved the book?

What is the kinetic energy of a 400kg house that is racing around a track at 17 meters per second?

A 5.0 kg object moving at 10 m/s on a frictionless surfaces collides with but does not stick to a 2.0 kg object that is initially at rest. The force on the 2 kg ball has a magnitude of 2000 N and it lasts for 0.01 s.

You are given four springs, one each of 3.5 , 6 , 8.5 , and 11 newtons per meter [N/m]. How do I find the smallest equivalent stiffness that can be made using only three of these springs?

A rock has a height of 4 cm, a length of 5 cm, and a width of 2 cm. what is the volume of the rock?

What is the weight of a 65 kg astronaut on mars?

When lava cools, what type of Rock forms?

A uniformly charged conducting sphere of 1.1 m diameter has a surface charge density of 6.2 µC/m2. (a) Find the net charge on the sphere. (b) What is the total electric flux leaving the surface of the sphere?

A blow-dryer and a vacuum cleaner each operate with a voltage of 120 V. The current rating of the blow-dryer is 12 A, while that of the vacuum cleaner is 5.7 A. Determine the power consumed by (a) the blow-dryer and (b) the vacuum cleaner.

4. A 40 kg child and a 30 kg child want to balance themselves on a 4 meter, 50 kilogramn see-saw. Where should the fulcrum be placed?