Tut.4 (sec. 20)

(a) How much work is done by gravity?

• 168 J

• -168 J

• -460 J

• 460 J

(b) How much energy is lost due to friction?

• 196 J

• -196 J

• 184 J

• -184 J

(c) How much work is done by the 100 N force?

• 500 J

• -500 J

• 0 J

• 100 J

(f) How much work is done by the Normal force?

• 168 J

• -168 J

• 0 J

• 500 J

(d) What is the change in kinetic energy of the crate?

• 148 J

• 484 J

• 516 J

• 852 J

(e) What is the speed of the crate after being pulled 5.00 m?

• 5.44 m/s

• 5.23 m/s

• 5.64 m/s

• 0 m/s

Q4. A 15 kg brick moves along an x axis. Its acceleration as a

function of its position is shown in the figure. The scale of

the figure’s vertical axis is set by as= 24.0 m/s2

. What is the

net work performed on the brick by the force causing the

acceleration as the brick moves from x= 0 to x=8.0 m?

• 1.1 kJ

• 1.2 kJ

• 1.3 kJ

• 1.4 kJ