Grade 12 Work Power And Energy Worksheets 2024 - Free Printable

Explanation:
Let’s go through each part step by step.

1. Fill in the blanks

a) *Work is the product of ________ and ________ in the direction of the force.*
→ Work = Force × Displacement (in the direction of the force)
So: force and displacement

b) *The S.I. unit for work is ________.*
→ From the table: Joule (J)
So: joule or J

c) *When force of ________ is used to ________ an object for a distance of ________ in the direction of force, work of 1 joule is done.*
→ By definition: 1 joule = 1 newton × 1 metre
So: 1 newton, move, 1 metre

d) *________ is the ability to do work.*
→ That’s the definition of energy

e) *When ________ of 1 joule is done in 1 second, power of ________ has been used.*
→ Power = Work / Time → 1 J / 1 s = 1 watt
So: work, 1 watt

f) *The S.I. unit for power is ________.*
→ From table: Watt (W)
So: watt or W

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2. Choose the correct answer

a) *The amount of work done is ________ the amount of energy used.*
→ In ideal cases (no losses), work done = energy transferred. So: equal to

b) *Power is the rate of ________.*
→ Power = work done per unit time → rate of doing work (or “work done”)

c) *The greater the work done, the ________ the power needed.*
→ Not necessarily — power also depends on *time*. But if time is fixed, more work means more power. However, the standard phrasing here expects: greater
(But careful: only if time is constant. Since this is basic level, they expect “greater”.)

d) *The two factors that affect the amount of work done are ________ and ________.*
→ From W = F × d → force and displacement

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3. Diagrams – Work done or not?

We need to decide if work is done in each case. Remember:
Work is done only when a force causes displacement in the direction of the force.

a) Person climbing stairs:
→ He applies upward force against gravity, and moves upward → displacement in direction of force → ✔ Work is done

b) Person holding a child (no movement):
→ Force is applied (to support weight), but no displacement → ✘ Work not done

c) Person pushing a wall (wall doesn’t move):
→ Force applied, but no displacement → ✘ Work not done

d) Person pushing a shopping cart (it moves):
→ Force applied forward, cart moves forward → ✔ Work is done

Now fill in:

a) Work is done
b) Work not done
c) Work not done
d) Work is done

Final Answer:
1. a) force, displacement
b) joule (J)
c) 1 newton, move, 1 metre
d) energy
e) work, 1 watt
f) watt (W)

2. a) equal to
b) doing work
c) greater
d) force, displacement

3. a) Work is done
b) Work not done
c) Work not done
d) Work is done