Question

If a car moving with 36 km/h increases its speed to 54 km/h in 10 seconds, find (i) acceleration and (ii) distance covered by the car in this time. *

3 points
If a car moving with 36 km/h increases its speed to 54 km/h in 10 seconds, find (i) acceleration and (ii) distance covered by the car in this time. *

3 points


An object travels 16 m in seconds and then another 16 m in 3 seconds. Is his motion uniform or non-uniform? *

1 point

Choose




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Answer 1

Ans. Initial velocity (u) = 36 km/h

When converted in m/s :-

Initial velocity (u) = 5/18×36

u = 10 m/s

Final velocity (v) = 54 km/h

When converted in m/s :-

Final velocity (v) = 5/18×54

v = 15 m/s

Time (t) = 10 s

(i) Acceleration (a) = (v-u)/t

a = (15-10)/10

a = 5/10

a = 0.5 m/s²

(ii) s = u×t + ½×a×t²

s = 10×10 + ½×0.5×10²

s = 100 + ½×0.5×10×10

s = 100 + 2.5×10

s = 100+25

Distance = 125 m

Sorry, but you have not given any time in third question for 1st motion but there is a 3 second time in the 2nd motion, so if any time except 3 seconds is given is given for 1st motion, it will be non-uniform motion and if the time for 1st motion is exactly 3 seconds it will be uniform motion.