Questions: Motors and Movement

Question 1

What does an electric motor do?

• A. It stores electricity for later use
• B. It converts electrical energy into rotational motion
• C. It converts motion into electricity
• D. It makes electricity flow faster

Answer: (B)

A motor converts electrical energy into mechanical motion — specifically, rotation (spinning). This spinning motion can then be transferred to wheels, gears, propellers, or other mechanisms to create useful movement. The device that does the opposite — converting motion into electricity — is called a generator.

Question 2

You can reverse the direction a motor spins by switching the positive and negative battery connections.

• T. True
• F. False

Answer: True

Reversing the polarity (swapping which wire connects to positive and which connects to negative) reverses the direction of the magnetic field inside the motor, which reverses the spin direction. This is how many toys and devices control forward and backward motion.

Question 3

A motor spins very fast but does not have much pushing force. How could an engineer make it push harder while accepting slower speed?

Model answer: Attach a small gear to the motor shaft and have it drive a larger gear. The larger gear will turn slower but with more force (torque). This is the same gear ratio trade-off used in bicycles — trading speed for power.

This connects motors to the gears topic. A motor's raw output is usually high-speed, low-force. For tasks like turning wheels on a toy car or lifting something, engineers use gear reduction to convert that high speed into the slower, more powerful rotation they need. Almost every motor in a real product has a gearbox attached to it.