BECE - Basic Education Certificate Examination Force, Work, and Energy Questions and Answers 1 — Questions and Answers
Question 1: A student pushes against a large, stationary brick wall with all their might for one minute, but the wall does not move. In physics terms, how much work has the student done on the wall?
- A large amount of work, because a large force was used.
- Zero work. (Correct answer)
- A small amount of work, because the time was short.
- It depends on the mass of the wall.
Correct answer: Zero work.
Work is calculated as Force multiplied by the distance moved in the direction of the force (W = F × d). Since the wall did not move, the distance (d) is zero. Therefore, no matter how much force was applied, the work done on the wall is zero.
Question 2: A battery-powered flashlight is switched on. Which of the following describes the main energy transformation that occurs?
- Electrical energy to chemical energy
- Kinetic energy to light energy
- Chemical energy to electrical energy, then to light and heat energy (Correct answer)
- Light energy to heat energy
Correct answer: Chemical energy to electrical energy, then to light and heat energy
A battery stores energy in chemical form. When the flashlight is turned on, this chemical energy is converted into electrical energy, which flows through the circuit. The bulb then transforms this electrical energy into light energy (its main purpose) and also heat energy as a byproduct.
Question 3: A mango hangs from a tree branch. What type of energy does it primarily possess due to its position?
- Kinetic energy
- Chemical energy
- Gravitational potential energy (Correct answer)
- Elastic potential energy
Correct answer: Gravitational potential energy
Potential energy is stored energy. Because the mango is at a height above the ground, it has gravitational potential energy. This is the energy it has stored due to its position in a gravitational field, which can be converted to kinetic energy if it falls.
Question 4: A boy pulls a cart with a force of 30 Newtons over a distance of 5 meters. How much work does the boy do?
- 6 Joules
- 35 Joules
- 150 Joules (Correct answer)
- 25 Joules
Correct answer: 150 Joules
The formula for work done is Work = Force × Distance. In this case, Force = 30 N and Distance = 5 m. Therefore, Work = 30 N × 5 m = 150 Joules.
Question 5: Which of the following is NOT an effect of a force acting on an object?
- Changing the direction of a moving object.
- Changing the mass of the object. (Correct answer)
- Changing the shape of the object.
- Changing the speed of a moving object.
Correct answer: Changing the mass of the object.
A force can cause an object to start moving, stop moving, change its direction, change its speed, or change its shape. However, applying a force does not change the mass of an object, which is the amount of matter it contains.
Question 6: What is the standard international (SI) unit for both work and energy?
- Newton
- Watt
- Pascal
- Joule (Correct answer)
Correct answer: Joule
The SI unit for both work and energy is the Joule (J). A Newton is the unit of force, a Watt is the unit of power, and a Pascal is the unit of pressure.
BECE - Basic Education Certificate Examination Force, Work, and Energy Questions and Answers 1
A student pushes against a large, stationary brick wall with all their might for one minute, but the wall does not move.
In physics terms, how much work has the student done on the wall?