China · Grade 9 · Practice Sheet 21

1. 1.

   Find the momentum of a 49 kg object moving at 18 m/s.

   Formula:Momentum

   $p = mv$

   View formula →
2. 2.

   A 40 kg object moves at 23 m/s. Find its kinetic energy.

   Formula:Kinetic Energy

   $KE = \tfrac{1}{2} m v^2$

   View formula →
3. 3.

   A circle has a radius of 11 cm. Find its area. (Use π ≈ 3.14159)

   Formula:Area of a Circle

   $A = \pi r^2$

   View formula →
4. 4.

   An object has mass 159.6 g and volume 21 cm³. Find its density.

   Formula:Density

   $\rho = \dfrac{m}{V}$

   View formula →
5. 5.

   A current of 4 A flows through a 27 Ω resistor. Find the voltage across it.

   Formula:Ohm's Law

   $V = I R$

   View formula →
6. 6.

   A right-angled triangle has legs of 19 cm and 6 cm. Find the length of the hypotenuse.

   Formula:Pythagorean Theorem

   $c = \sqrt{a^2 + b^2}$

   View formula →
7. 7.

   A current of 3.3 A flows through a 8 Ω resistor. Find the voltage across it.

   Formula:Ohm's Law

   $V = I R$

   View formula →
8. 8.

   A device runs at 165 V drawing 3.1 A. Find its power consumption.

   Formula:Electrical Power

   $P = V I$

   View formula →
9. 9.

   A force of 23 N moves an object 14 m in the direction of the force. Find the work done.

   Formula:Work Done

   $W = F d$

   View formula →
10. 10.

    ¥2,900 is invested at 4% simple interest per year for 5 years. Find the interest earned.

    Formula:Simple Interest

    $I = \dfrac{P \times r \times t}{100}$

    View formula →
11. 11.

    A device runs at 23 V drawing 7.2 A. Find its power consumption.

    Formula:Electrical Power

    $P = V I$

    View formula →
12. 12.

    A cone has base radius 2 cm and height 5 cm. Find its volume. (π ≈ 3.14159)

    Formula:Volume of a Cone

    $V = \tfrac{1}{3} \pi r^2 h$

    View formula →
13. 13.

    ¥2,200 is invested at 6% compound interest per annum for 4 years. Find the final amount (to 2 d.p.).

    Formula:Compound Interest

    $A = P\left(1 + \dfrac{r}{100}\right)^{t}$

    View formula →
14. 14.

    A train moves at 81 km/h for 5.4 hours. How far does it travel?

    Formula:Distance from Speed & Time

    $d = v \times t$

    View formula →
15. 15.

    ¥2,000 is invested at 6% compound interest per annum for 4 years. Find the final amount (to 2 d.p.).

    Formula:Compound Interest

    $A = P\left(1 + \dfrac{r}{100}\right)^{t}$

    View formula →
16. 16.

    A value changes from 57 to 255. Find the percentage change (to 2 d.p.).

    Formula:Percentage Change

    $\%\,\text{change} = \dfrac{\text{new} - \text{old}}{\text{old}} \times 100$

    View formula →
17. 17.

    A right-angled triangle has legs of 7 cm and 12 cm. Find the length of the hypotenuse.

    Formula:Pythagorean Theorem

    $c = \sqrt{a^2 + b^2}$

    View formula →
18. 18.

    Find the gravitational potential energy of a 42 kg object raised 16 m. (g = 9.8 m/s²)

    Formula:Gravitational Potential Energy

    $PE = mgh$

    View formula →
19. 19.

    A cone has base radius 12 cm and height 21 cm. Find its volume. (π ≈ 3.14159)

    Formula:Volume of a Cone

    $V = \tfrac{1}{3} \pi r^2 h$

    View formula →
20. 20.

    A train moves at 77 km/h for 5.2 hours. How far does it travel?

    Formula:Distance from Speed & Time

    $d = v \times t$

    View formula →

© FormulaWon — formulawon.app · Answers & step-by-step working available on the solutions sheet.