Question

A car travels 15 km in 20 minutes. What is the speed in s-1 and h-1​

Answer 1

The following are the given values in the question :-

distance the car travells (s) = 15 km

time the car travelled (t) = 20 minutes

Now as asked in the question, we need speed of car

formula for speed of car is :-

Speed (v) = distance (s)/time (t)

(i) When time is in seconds.

time taken (t) = 20 x 60 = 1200 secs.

so, speed = 15 km/1200 s = 0.0125 km s^-1

(ii) When time is in hours.

time taken (t) = 20/60 = 1/3 hours.

so, speed = 15 km/1/3 hrs = 45 km hrs^-1

pls mark as brainliest if you find this helpful!

Answer 2

Answer:

The speed of the car :-

• 45 km/hr
• 12.5 m/sec

Explanation:

SI unit of speed = km/hr or m/s

• Distance covered by car = 15 km
• Time taken by car = 20 min = 20/60 hr = 1/3 hr.

$Speed = \frac{distance \: in \: km}{time \: in \: hr}$

$= > Speed = \frac{15}{ \frac{1}{3} } = 15 \times 3 = 45 \frac{km}{hr}$

The speed of car is 45 km/ hr.

• Distance covered by car = 15 km = 15 × 1000 m.
• Time taken by the car = 20 min = 20 × 60 sec.

$Speed = \frac{distance \: in \: m}{time \: in \: sec}$

$= > Speed = \frac{15 \times 1000}{20 \times 60} = 12.5 \frac{m}{sec}$

The speed of car is 12.5 m/sec.