The battery in an electric car needs to be recharged - AQA - GCSE Physics - Question 8 - 2022 - Paper 1

The equation is:

a = \frac{\Delta v}{t}

Given:

• Final velocity (v) = 28 m/s
• Initial velocity (u) = 0 m/s
• Acceleration (a) = 20 m/s²

Using the formula:

$a = \frac{v - u}{t}$

Substituting the known values:

$20 = \frac{28 - 0}{t}$

Rearranging gives:

t = \frac{28}{20} = 1.4 , s$$

Using the equation of motion:

$v^2 = u^2 + 2as$

where:

• u = 0 m/s,
• a = 10 m/s²,
• s = 605 m.

Substituting the values:

$v^2 = 0 + 2 \times 10 \times 605$

This simplifies to:

$v^2 = 12100$

Taking the square root gives:

$v = 110 \, m/s$

The equation is:

$W = F \times s$

Given:

• Distance (s) = 7.5 km = 7500 m
• Force (F) = 4000 N

Using the equation:

$W = F \times s$

Substituting the values:

$W = 4000 \times 7500$

Calculating gives:

$W = 30000000 \, J$