Question

A particle is projected upwards with Speed 2 metre per second square at time t is equal to zero at what time will be the speed of particle be half the initial speed​

Answer 1

Answer:

• At time t = 0.102 sec velocity of particle will become half of its initial velocity.

Explanation:

• Initial velocity of particle (at time t=0) is u = 2 m/s

Particle is moving upward.

• Acceleration due to gravity for motion of particle would be taken as, g = -9.8 m/s²

[ Negative acceleration due to gravity because particle is moving upward]

we need to find the time when the speed of particle will be half the initial speed.

means., final velocity, v = 1 m/s

Using the first equation of motion

→ v = u + a t

→ 1 = 2 + (-9.8) × t

→ 1 - 2 = -9.8  t

→ -1 = -9.8  t

→ t = 0.102 sec     [ Approx. ]

Therefore,

• At time t = 0.102 seconds., the velocity of the particle will become half of the initial velocity.

Answer 2

u = 2 m/s

v = 1 m/s

a = -9.8 m/s² (body is projected upwards)

By using the First Equation Of Motion:

v = u + at

→ 1 = 2 - 9.8t

→ 9.8t = 1

→ t = 1/9.8

→ t = 0.1 seconds (approx)