Colombia · Grado 9 · Practice Sheet 18

1. 1.

   A circle has a radius of 20 cm. Find its area. (Use π ≈ 3.14159)

   Formula:Area of a Circle

   $A = \pi r^2$

   View formula →
2. 2.

   A current of 4.9 A flows through a 20 Ω resistor. Find the voltage across it.

   Formula:Ohm's Law

   $V = I R$

   View formula →
3. 3.

   A 35 kg object moves at 16 m/s. Find its kinetic energy.

   Formula:Kinetic Energy

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

   View formula →
4. 4.

   $3,600 is invested at 8% simple interest per year for 5 years. Find the interest earned.

   Formula:Simple Interest

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

   View formula →
5. 5.

   Find the circumference of a circle whose radius is 10 m. (Use π ≈ 3.14159)

   Formula:Circumference of a Circle

   $C = 2\pi r$

   View formula →
6. 6.

   Find the momentum of a 23 kg object moving at 7 m/s.

   Formula:Momentum

   $p = mv$

   View formula →
7. 7.

   An object has mass 90 g and volume 50 cm³. Find its density.

   Formula:Density

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

   View formula →
8. 8.

   $204 is shared in the ratio 2 : 4. Find each share.

   Formula:Dividing in a Ratio

   $\text{share} = \dfrac{\text{part}}{\text{total parts}} \times T$

   View formula →
9. 9.

   A cone has base radius 9 cm and height 4 cm. Find its volume. (π ≈ 3.14159)

   Formula:Volume of a Cone

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

   View formula →
10. 10.

    $900 is invested at 3% simple interest per year for 2 years. Find the interest earned.

    Formula:Simple Interest

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

    View formula →
11. 11.

    Find the circumference of a circle whose radius is 16 m. (Use π ≈ 3.14159)

    Formula:Circumference of a Circle

    $C = 2\pi r$

    View formula →
12. 12.

    A car travels 213 km in 3 hours. Find its average speed.

    Formula:Speed

    $v = \dfrac{d}{t}$

    View formula →
13. 13.

    Find the force needed to accelerate a 32 kg mass at 8.8 m/s².

    Formula:Newton's Second Law

    $F = ma$

    View formula →
14. 14.

    A device runs at 68 V drawing 9.6 A. Find its power consumption.

    Formula:Electrical Power

    $P = V I$

    View formula →
15. 15.

    A right-angled triangle has legs of 11 cm and 11 cm. Find the length of the hypotenuse.

    Formula:Pythagorean Theorem

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

    View formula →
16. 16.

    A value changes from 46 to 189. 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.

    Find the gravitational potential energy of a 36 kg object raised 27 m. (g = 9.8 m/s²)

    Formula:Gravitational Potential Energy

    $PE = mgh$

    View formula →
18. 18.

    A value changes from 23 to 251. Find the percentage change (to 2 d.p.).

    Formula:Percentage Change

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

    View formula →
19. 19.

    A right-angled triangle has legs of 11 cm and 19 cm. Find the length of the hypotenuse.

    Formula:Pythagorean Theorem

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

    View formula →
20. 20.

    A device runs at 6 V drawing 4.1 A. Find its power consumption.

    Formula:Electrical Power

    $P = V I$

    View formula →

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