RC EXAM GEAS 43

In thermodynamics, our attention is focused on which form of energy?

• Internal energy

• Total energy

• Kinetic energy

• Potential energy

Select a correct statement of the first law if kinetic and potential energy changes are negligible.

• Net heat transfer minus net work equals internal energy change for a cycle.

• Net heat transfer equals net work for a cycle.

• Heat transfer minus work equals internal energy for a process.

• Heat transfer equals work for a process.

For which of the following situations is the net force acting on a particle necessarily equal to zero?

• The particle has constant angular momentum.

• The particle is traveling at constant velocity around a circle.

• The particle has constant kinetic energy.

• The particle has constant linear moment.

The first derivative of kinetic energy with respect to time:

• Work

• Power

• Force

• Momentum

A mass of 10 kg is suspended from a vertical spring with a spring constant of 10 N/m. What is the period of vibration?

• 0.60 s

• 6.3 s

• 0.30 s

• 0.90 s

A charge q = + 3.0 nC is placed at a location which the electric field strength is 400 N/C. Find the force felt by q.

• 1.2 x 10-6 N

• 3.2 x 10-6 N

• 4.2 x 10-6 N

• 2.2 x 10-6 N

An inclined force, F, is applied to a block of mass m. What is the minimum coefficient of static friction between the block and the ramp surface such that no motion occurs?

• F/mg

• 4F/(3F + 5mg)

• (F tan θ)/mg

• 3F/(4F + 5 mg)

The elevator in a 12-storey building has a mass of 1000 kg. Its maximum velocity and maximum acceleration are 2 m/s and 1 m/s², respectively. A passenger with a mass of 75 kg stands on a bathroom scale in the elevator as the elevator ascends at its maximum acceleration. What is the scale reading just as the elevator reaches maximum acceleration?

• 811 N

• 75 N

• 886 N

• 150 N

A projectile is fired from a cannon with an initial velocity of 1000 m/s and at an angle of 30° from the horizontal. What is the distance from the cannon will the projectile strike the ground if the point of impact is 1500 m below the point of release?

• 8200 m

• 67300 m

• 90800 m

• 78200 m

A projectile whose mass is 10 g is fired directly upward from ground level with an initial velocity of 1000 m/s. Neglecting the effect of air resistance, what will be the speed of the projectile when it impacts the ground?

• 1414 m/s

• 707 m/s

• 1000 m/s

• 981 m/s