A 10-kilogram block with an initial velocity of 10 m/s slides 10 meters across a horizontal surface and comes to rest. It takes the block 2 seconds to stop. The stopping force acting on the block is about
A) 5 N.
B) 10 N.
C) 25 N.
D) 50 N.
E) none of the above
Answer: D
You might also like to view...
The slope of a tangent line at a given time value on a position versus time graph gives
A) instantaneous velocity. B) average velocity. C) instantaneous acceleration. D) average acceleration E) none of the given answers.
Why are elements with even numbers of protons more abundant, on average, than elements with odd numbers of protons?
A) because when elements split in a fission reaction, they prefer to split with all the protons paired B) because elements are mainly made in fusion reactions with hydrogen nuclei C) because elements are mainly made in fusion reactions with helium nuclei D) There's no explanation; it's something of a mystery to be explained or it may be a coincidence.
An ambulance with its siren on is heading due east along a straight road at 60 mph. A car is also moving along the same road. In which case will the driver of the car perceive the frequency of the siren to be lowest?
a. The car is moving east at 65 mph and is behind the ambulance b. The car is moving west at 65 mph and is behind the ambulance. c. The car is moving east at 65 mph and is in front of the ambulance. d. The car is moving west at 65 mph and is in front of the ambulance.
A series of n uncharged concentric shells surround a small central charge q. The charge distributed on the outside of the nth shell is
a. ?nq. b. ?(ln n)q. c. +q. d. +(ln n)q. e. +nq.