A student releases a marble from the top of a 210cm ramp. The marble increases speed steadily and reaches the bottom of the ramp with a speed of
70cm/s. Determine all unknowns and answer the following question.
Si
210
cm/s
S
140
cm/s
Sf
70
cm/s 7
d =
unity
t =
unit
How long did the marble take to reach the bottom of the ramp?
unit

Pleas

The percent efficiency of a machine can never be 100% (or greater), because in the real world some energy is always converted into a. heat b. work c. input force d. output force

Match these items. 1. coulombs __force 2. ohms __emf 3. centimeters __resistance 4. newtons __charge 5. volts __length

Two cannon balls weighing 18 kg and 24 kg are chained together and fired horizontally with a velocity of 165 m/s from the top of a 21-m wall. the chain breaks during the flight of the cannonballs and the 18-kg cannonball strikes the ground at t = 1.5 s, at a distance of 240 m from the foot of the wall, and 7 m to the right of the line of fire. determine the position of the other cannonball at that instant. neglect the resistance of the air.