Question

27. A cannon is to fire up to 500 m horizontally. What
should be the angle of projection, if the shells are
fired with a velocity of 100 m/s? (g = 10 m/s2)
​

Answer 1

Answer:

Given V=100ms and Range R=500m and g=10m/s

2

Let the angle of projection is θ with the horizontal.

Horizontal velocity V

H

=Vcosθ=100cosθ

Vertical velocity V

V

=Vsinθ=100sinθ

∴ Time of flight =

g

2V

V

=

g

2×100sinθ

⇒ Range =V

H

×Time of flight

⇒

g

100cosθ×2×100sinθ

=500 ⇒sin2θ=

2

1

⇒2θ=30

o

⇒θ=15 °