Question

a body is projected horizontally with speed 20 metre per second what will be its speed after 5 second

Answer 1

Since, body is projected horizontally with a velocity of 20m/s.

ux = 20m/s

ax = 0

So, vx = 20m/s for all time.

Along vertical axis,

uy = 0

t = 5

ay = 10m/s2

vy =?

vy = uy +ayt

=> vy = 0 + 10*5= 50m/s

So, magnitude of velocity of body after 5s

√{(50)²+(20)²}m/s
=√2900 m/s
=53.851 m/s
= 54 m/s (approx)

Answer 2

Answer:

          54 m/s

Since, body is projected horizontally with a velocity of 20m/s.

ux = 20m/s

ax = 0

So, vx = 20m/s for all time.

Along vertical axis,

uy = 0

t = 5

ay = 10m/s2

vy =?

vy = uy +ayt

=> vy = 0 + 10*5= 50m/s

So, magnitude of velocity of body after 5s

V =√vx² + vy²

√{(50)²+(20)²}m/s

=√2900 m/s

=53.851 m/s

= 54 m/s (approx)