Question 3 A 75 kg block is pulled by a rope at a constant speed over a rough floor for 4 meters. The force of tension
is 8 Newtons. How much energy is disspated by friction?

Africtionless piston-cylinder contains 50 l of saturated liquid r-134a. the piston has a mass and an area resulting in an applied pressure of 500 kpa on the refrigerant. the refrigerant is now heated until its temperature rises to 70∘c. calculate the work (in kj) done during this process.

Positrons are spontaneously emitted from the nuclei of

If you wanted to move an electron from the positive to the negative terminal of the battery, how much work w would you need to do on the electron? enter your answer numerically in joules.