Practise questions · Salam Academy

SA-9709-P4-EW3-0022 marksL1 FoundationCalculatorWork–energy

A car of mass

1200

kg travelling at

25\ \text{m s}^{-1}

brakes on a level road with a constant braking force of

7500

N. Use the work–energy principle to find its stopping distance.

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P4-EW3-0091 markL1 FoundationCalculatorFinding resistances

A particle slides down a rough slope from rest. Which equation is correct?

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P4-EW3-0014 marksL2 StandardCalculatorWork–energy

A block of mass

5

kg slides from rest

10

m down a rough slope, descending

6

m vertically. A constant friction force of

15

N acts. Find its speed at the bottom, correct to 3 significant figures.

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P4-EW3-0034 marksL2 StandardCalculatorFinding resistances

A ball of mass

0.5

kg is dropped from rest from a height of

20

m and hits the ground at

18\ \text{m s}^{-1}

. Find the work done against air resistance and the average resistance force.

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P4-EW3-0044 marksL2 StandardCalculatorFinding resistances

A particle of mass

3

kg is projected at

10\ \text{m s}^{-1}

along a rough horizontal floor and comes to rest after travelling

12.5

m. Find the friction force and the coefficient of friction.

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P4-EW3-0054 marksL2 StandardCalculatorWork–energy

A cyclist and bicycle of total mass

75

kg freewheel down a hill, descending

20

m vertically. Their speed increases from

4\ \text{m s}^{-1}

to

16\ \text{m s}^{-1}

. Find the work done against resistances.

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P4-EW3-0084 marksL2 StandardCalculatorWork–energy

A car of mass

1000

kg speeds up from

5\ \text{m s}^{-1}

to

15\ \text{m s}^{-1}

over

400

m of level road against a constant resistance of

500

N. Find the work done by the engine, in kJ.

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P4-EW-0055 marksL3 ExamCalculatorWork–energy

A sledge of mass

40

kg starts from rest and slides

30

m down a slope, descending

12

m vertically. A constant friction force of

60

N acts. Find its speed at the bottom, correct to 3 significant figures.

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P4-EW-0124 marksL3 ExamCalculatorWork–energy

A cyclist and bicycle of total mass

80

kg speed up from

5\ \text{m s}^{-1}

to

10\ \text{m s}^{-1}

over

200

m of level road against a constant resistance of

20

N. Find the work done by the cyclist.

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P4-EW3-0065 marksL3 ExamCalculatorWork–energy

A crate of mass

20

kg is pulled from rest

15

m up a rough slope by a rope parallel to the slope. The crate rises

3

m vertically, the friction force is

40

N, and its final speed is

3\ \text{m s}^{-1}

. Find the work done by the rope.

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P4-EW3-0074 marksL3 ExamCalculatorFinding resistances

A particle of mass

2

kg is projected at

10\ \text{m s}^{-1}

up a line of greatest slope of a rough plane inclined at

30^\circ

. It travels

8

m up the plane before stopping. Find the friction force.

Salam Academy Original Practice · Proposed mark scheme

SA-9709-P4-EW3-0104 marksL3 ExamCalculatorWork–energy

A skier of mass

60

kg starts from rest and descends

50

m vertically while travelling

400

m along the slope, against a constant resistance of

45

N. Find her speed at the bottom.

Salam Academy Original Practice · Proposed mark scheme

Question bank