The force required to maintain an object at a constant speed in free space
is equal to
the mass of the object
the weight of the object
the force required to stop it
none of the above
Two teams are having a
tug-of-war, using a nylon rope with practically no mass. Team A (on the left) is
winning--both teams are accelerating to the left. What can you say about the
tension in the rope?
It is higher on the left than on the right.
It is higher on the right than on the left.
It is constant throughout the rope.
slide a block of ice down a 45° ramp. There is no
friction between the ice and the ramp. The acceleration of the ice block down
the ramp will be
still equal to
the normal acceleration of gravity, 9.8 m/s2.
Ralph told me he was thinking about the penny and feather falling in
a vacuum. The penny and feather both fell at the same rate. He asked,
"Does this mean that the force on the penny and the force on the feather
are equal?" How would you answer his question? Be sure to explain
No, the forces are not equal. The *accelerations* are equal, but since the net force = mass x acceleration, the net forces will not be equal. In this case, each object's net force is simply provided by its weight, w = mg, so you can see that the heavier object will have a larger net force.