Question

A boy aims a gun at a bird from a point at a horizontal distance of 100m. If the gun can impart a velocity of 500m/sec to the bullet, at what height above the bird must he aim his gun inorder to hit it​

Answer 1

Answer:

Explanation:

GIVEN ;-

⇒ Distance of a person from the  bird  is = 100 m

⇒ Speed of bullet                                  = 500 m /s

TO FIND ;-

⇒ what height of the bird he should aim his gun to hit ?

SOL ;-

⇒ Initial velocity of the bullet = 500 m / s

⇒ Range = 100 × 2 = 200 m

                        ⇒  Now we got the range.

⇒ Velocity of the bullet =  500 m / s

⇒ Distance from gun to bird in horizontal = x = 100 m

                  ⇒ Now let us find the time taken for this distance

⇒ Time travelled =  Distance / velocity 

                       =  100         /    500 

                       =   1 / 5 seconds

We got the time travelled by the bullet in horizontal  way , Let us find it in vertical time using the time 1 / 5 sec.

⇒ y = uyt + 1/2 gt²

     =  0 + 1 / 2 × 10 × 1 / 25

     = 1 / 5 m   ⇒ 20 cm

So the gun must be aimed at 20 cm.

Answer 2

Answer: 0.2m or 20cm

Explanation:

You can use the given formula:

D= u√2H/g

Where D is the horizontal distance, u is initial velocity, H is height and g is acceleration due to gravity.

Putting values in the above formula,

100= 500√2H/10

1/5= √2H/10

Squaring both sides,

1/25=2H/10

H= 10/50

H= 0.2m or 20cm

Hope it helped....

Cheers..!!!