A driver, traveling at 22 m/s, slows down her 2000 kg truck to stop for a red light. What work is done on the truck by the friction force exerted by the road on the truck?
A) -2.2 × 104 J
B) -4.4 × 104 J
C) -4.8 × 105 J
D) -9.7 × 105 J
C
You might also like to view...
A satellite is in a circular orbit 600 km above the Earth's surface. The acceleration of gravity is 8.21 m/s2 at this altitude. The radius of the Earth is 6 400 km. Determine the speed of the satellite, and the time to complete one orbit around the Earth
Calorimetry: A 360-g metal container, insulated on the outside, holds 180.0 g of water in thermal equilibrium at 22.0°C. A 24.0-g ice cube, at the melting point, is dropped into the water, and when thermal equilibrium is reached the temperature is 15.0°C. Assume there is no heat exchange with the surroundings. For water, the specific heat capacity is 4190 J/kg ? K and the heat of fusion is 3.34 × 105 J/kg. What is the specific heat capacity of the metal of the container?
A. 1700 J/kg ? K B. 970 J/kg ? K C. 2300 J/kg ? K D. 2800 J/kg ? K E. 3300 J/kg ? K
A 10 kg mass is attached to the end of a 2.00 m brass rod with a 1 mm diameter. If the tensile modulus of brass is 
then the frequency of the simple harmonic motion of the mass is
A. 6.20 Hz. B. 7.51 Hz. C. 7.95 Hz. D. 8.21 Hz. E. 9.51 Hz.
If an object moves with constant acceleration, its velocity must
A) be constant also. B) change by the same amount each second. C) change by varying amounts depending on its speed. D) always decrease.