53.2k views
4 votes
A car increases its speed from 20km/h to 50 km/h in 10s. Its acceleration is :

A.30 m/s2
B.3 m/s2
C.18 m/s2
D.none of these

1 Answer

6 votes

Final answer:

To calculate acceleration, convert the car's change in speed from km/h to m/s and then use the formula a = Δv/Δt. The acceleration is found to be 0.833 m/s², which is not listed among the given options, making the correct answer D. none of these.

Step-by-step explanation:

The question relates to the concept of acceleration in Physics. To find the acceleration, you use the formula a = Δv/Δt, where 'a' is acceleration, 'Δv' is the change in velocity, and 'Δt' is the change in time. The initial speed of the car is 20 km/h which we convert to meters per second (20 km/h × (1000 m/km) / (3600 s/h) = 5.56 m/s). The final speed is 50 km/h, converted similarly to 13.89 m/s. The change in velocity (Δv) is 13.89 m/s - 5.56 m/s = 8.33 m/s. Given that the time interval (Δt) is 10 seconds, we calculate the acceleration as:

a = Δv/Δt = 8.33 m/s / 10 s = 0.833 m/s².

The correct answer is D. none of these, since the computed acceleration of 0.833 m/s² is not listed among the given options.

User Shrenik Shah
by
7.9k points