Question

E. a distance of 5 multiply 10^5 cm in 2 multiply 10^-5 seconds

Answer 1

The speed is 900,000,000 km/h

Explanation:

The ratio of distance covered to time taken gives the speed of an object

`Speed, \ v = (Distance, \ d)/(Time, \ t)`

Given that the distance covered, d = 5 × 10⁵ cm

The time to travel the given distance, t = 2 × 10⁻⁵ seconds

Therefore;

`Speed, \ v = (5 * 10^(5) \ cm)/(2 * 10^(-5) \ s) = 2.5 * 10 ^(10) \ cm/s`

In km/h, we have;

1 cm = 0.00001 km

∴ v = 2.5 × 10¹⁰ cm/s × 1 km/(100,000 cm) × 3,600 s/h = 900,000,000 km/h

The speed is 2.5 × 10¹⁰ cm/s or 900,000,000 km/h.