Question

(C) Solve the given numerical problems.
1. A man is running on the straight road with the uniform velocity of 3m/s. calculate acceleration produced by him
​

Answer 1

Answer:

Given,

Velocity of man =

u

=u

i

^

Let the velocity of rain =

v

=x

i

^

+y

j

^

Now, in first case velocity of rain with respect

to man =

V

R

=

v

−

u

=(x−u)

i

^

+y

j

^

Given that It x− component is zero as

rain is falling vertically down, and y component

is along −ve direction

So, x−u=0

⇒x=u

∴ velocity of rain =u

i

^

+y

j

^

In second case when be will doobles his speed velocity of rain with respect to man =

V

R

⇒

V

R

=

v

−

u

=u

i

^

+y

j

^

−2u

i

^

=−u

i

^

+y

j

^

Now this case rain is coming at an angle θ to the vertical

∴tanθ=

y

−u

⇒y=

tanθ

−u

∴ velocity of rain with respect to ground

=

V

=x

i

^

+y

j

^

=u

i

^

−

tanθ

y

j

^

∴ Option B is correct

solution

Answer 2

Answer:

Acceleration = 0

Explanation:

Change is velocity/time = Acceleration

(v - u)/ t = a (Since velocity is constant / no change in velocity / uniform velocity)

0/t = 0