EXAM 11th edition by Hugh D Young
You swing a bat and hit a heavy box with a force of 1500 N. The force the box exerts on the bat
is? - ANSexactly 1500 N whether or not the box moves
When a rigid body rotates about a fixed axis, all the points in the body have the same -
ANSangular acceleration
A 1000.0 kg car is moving at a 15 km/hr. If a 2000.0 kg truck has 18 times the kinetic energy of
the car, how fast is the truck moving? - ANS45 km/hr (use KE= 1/2mV^2)
A ball drops some distance and gains 30 J of kinetic energy. Do not ignore air resistance. How
much gravitational potential energy did the ball lose? - ANSless than 30 J
A box of mass m is pressed against (but is not attached to) an ideal spring of force constant k
and negligible mass, compressing the spring a distance x. After it is released, the box slides up
a frictionless incline as shown in the figure and eventually stops. If we repeat this experiment
but instead use a spring having force constant 2k - ANSAll of the above choices are correct: the
box will go up the incline twice as high as before; just as it moves free of the spring, the kinetic
energy of the box will be twice as great as before; just as it moves free of the spring, the speed
of the box will be the sqaure root of 2 times greater as before
Is it possible for a system to have negative potential energy? - ANSYes, since the choice of the
zero of potential energy is arbitrary
Two objects having masses m1 and m2 are connected to each other as shown in the figure and
are released from rest. There is no friction on the table surface or in the pulley. The masses of
the pulley and the string connecting the objects are completely negligible. What must be true
about the tension T in the string just after the objects are released? - ANST<m2g
If the temperature of a fixed amount of an ideal gas is increased, it necessarily follows that -
ANSthe speed of the gas molecules will increase
Two objects are thrown from the top of a tall building. One is thrown up, and the other is thrown
down, both with the same initial speed. What are their speeds when they hit the street? -
ANSthey are traveling at the same speed