Physics Answers

1. A box of mass 5 kg is accelerated from rest across a floor at a rate of 2 m/s2  for 7 s. Find the net work done on the box.

A car running at a speed of 72 km/h is to be stopped in exactly 10 seconds. Find the uniform deceleration needed.

A patient transport vehicle is running at a speed of 80 m/s. It is the decelerated at the rate of 10m/s. When will it stop?

- Two small silver spheres each with a mass of 100gm are separated by 1 m. Calculate the number of electrons that must be transferred from one to the other to produce an attractive force of 104 N between the spheres.

A sample of air has a temperature of 40.0◦C and occupies a volume of 2.30ℓ. At what temperature would it occupy a volume of 6.50ℓ?

A steel bridge is 625m long when the temperature is 0◦C. If the bridge did not have any expansion joints, how much longer would the bridge be on a hot summer day when the temperature is 35◦C? (Use the linear co¨efficient of expansion for iron.)

1.5000 L of antifreeze at 50.000°C cools to -26.000°C. What is the final volu

A Carnot heat engine receives heat at T1 and rejects the waste heat to the environment at T2. The

entire work output of the heat engine is used to drive a Carnot refrigerator that removes heat

from the cooled space at 258 K at a rate of 400 kJ/min and rejects it to the same environment at

T2. Determine

(a) The rate of heat supplied to the heat engine and

(b) The total rate of heat rejection to the environment.

How much water will spill from a 5.00 L vat if the temperature increased by 35.0°C?

8. If the real normalized functions f(x) and g(x) are not orthogonal, show that their sum f(x) +g(x) and their difference f(x)−g(x) are orthogonal.