1. Which is NOT a unit of force?
A. Dyne B. Joules C. Newton D. Pound
2. What force is always directed opposite to the motion of an object?
A. Friction
B. Gravitational
C. Magnetic
D. Tension
3. Which surface would be easiest for a bicycle to move?
A. Sand
B. Grass
C. Muddy road
D. Concrete road
4. What type of forces holds between two celestial bodies like the Sun and Earth?
A. Applied
B. Gravitational
C. Magnetic
D. Tension ​