Question

A man covers 5m in 2 seconds, taking a turn he covers 6m in next 4 seconds and 3 cm in another 6 seconds. Then his motion is​

Answer 1

Answer:

Let the initial velocity of the body be u m/s; and the constsnt acceleration be a m/s². Then displacemet (distance covered) of the body after t second is given by

s = u t + ½ a t² ———————————-(1)

The body covers 20 m in 2s and 80 m in 4 s.

20 = u×2 + ½ a 2²; => 20 = 2 u + 2 a

u + a = 10 —————————————(2)

80 = u×4 + ½ a 4²; => 80 = 4 u + 8 a; this gives,

u + 2 a = 20 ——————————————(3)

Solving (2) and (3) for u and a we get

u = 0 m/s and a = 10 m/s² ————————(4)

To obtain the distance covered in the next 4s we need to find the velocity at the beginning of this interval using,

v = u + a t => v = 0 m/s + 10 m/s² ×4s = 40m/s

s = u t + ½ a t²

Substituting various values we get

s = 40×4 +½ ×10×4² = 160 + 80= 240 m

The body will cover 240 m in the next 4 seconds

Answer 2

Answer:

Let the initial velocity of the body be u m/s; and the constsnt acceleration be a m/s². Then displacemet (distance covered) of the body after t second is given by

s = u t + ½ a t² ———————————-(1)

The body covers 20 m in 2s and 80 m in 4 s.

20 = u×2 + ½ a 2²; => 20 = 2 u + 2 a

u + a = 10 —————————————(2)

80 = u×4 + ½ a 4²; => 80 = 4 u + 8 a; this gives,

u + 2 a = 20 ——————————————(3)

Solving (2) and (3) for u and a we get

u = 0 m/s and a = 10 m/s² ————————(4)

To obtain the distance covered in the next 4s we need to find the velocity at the beginning of this interval using,

v = u + a t => v = 0 m/s + 10 m/s² ×4s = 40m/s

s = u t + ½ a t²

Substituting various values we get

s = 40×4 +½ ×10×4² = 160 + 80= 240 m

The body will cover 240 m in the next 4 seconds