Brazil · Ano 9 · Practice Sheet 21

1. 1.

   A wave has frequency 459 Hz and wavelength 1.21 m. Find its speed.

   Formula:Wave Speed

   $v = f\lambda$

   View formula →
2. 2.

   Find the volume of a sphere of radius 5 cm. (π ≈ 3.14159)

   Formula:Volume of a Sphere

   $V = \tfrac{4}{3} \pi r^3$

   View formula →
3. 3.

   A wave has frequency 274 Hz and wavelength 1.96 m. Find its speed.

   Formula:Wave Speed

   $v = f\lambda$

   View formula →
4. 4.

   Solve for x: 6x + 8 = 74.

   Formula:Solving a Linear Equation

   $x = \dfrac{c - b}{a}$

   View formula →
5. 5.

   A force of 285 N acts on an area of 4.6 m². Find the pressure.

   Formula:Pressure

   $P = \dfrac{F}{A}$

   View formula →
6. 6.

   Find the momentum of a 16 kg object moving at 30 m/s.

   Formula:Momentum

   $p = mv$

   View formula →
7. 7.

   A cone has base radius 9 cm and height 10 cm. Find its volume. (π ≈ 3.14159)

   Formula:Volume of a Cone

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

   View formula →
8. 8.

   Solve for x: 8x + 20 = 100.

   Formula:Solving a Linear Equation

   $x = \dfrac{c - b}{a}$

   View formula →
9. 9.

   A current of 7.2 A flows through a 19 Ω resistor. Find the voltage across it.

   Formula:Ohm's Law

   $V = I R$

   View formula →
10. 10.

    R$ 4,000 is invested at 4% 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.

    R$ 102 is shared in the ratio 5 : 1. Find each share.

    Formula:Dividing in a Ratio

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

    View formula →
12. 12.

    R$ 1,800 is invested at 4% compound interest per annum for 5 years. Find the final amount (to 2 d.p.).

    Formula:Compound Interest

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

    View formula →
13. 13.

    A car travels 370 km in 5 hours. Find its average speed.

    Formula:Speed

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

    View formula →
14. 14.

    Find the gravitational potential energy of a 14 kg object raised 14 m. (g = 9.8 m/s²)

    Formula:Gravitational Potential Energy

    $PE = mgh$

    View formula →
15. 15.

    A cylinder has radius 8 cm and height 7 cm. Find its volume. (π ≈ 3.14159)

    Formula:Volume of a Cylinder

    $V = \pi r^2 h$

    View formula →
16. 16.

    Find the momentum of a 29 kg object moving at 19 m/s.

    Formula:Momentum

    $p = mv$

    View formula →
17. 17.

    A device runs at 46 V drawing 7.4 A. Find its power consumption.

    Formula:Electrical Power

    $P = V I$

    View formula →
18. 18.

    A force of 114 N moves an object 30 m in the direction of the force. Find the work done.

    Formula:Work Done

    $W = F d$

    View formula →
19. 19.

    An object has mass 276.9 g and volume 39 cm³. Find its density.

    Formula:Density

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

    View formula →
20. 20.

    A current of 2.4 A flows through a 9 Ω resistor. Find the voltage across it.

    Formula:Ohm's Law

    $V = I R$

    View formula →

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