[Assume g = 10 m/s^2]
If a girl is running along a straight road with a uniform velocity 1.5 m/s, find her acceleration.
Answers
Answer:
b is correct answer
Explanation:
Motion in a Plane
Relative Motion in 2 Dimension
A man running along a strai...
PHYSICS
A man running along a straight road with uniform velocity
u
=u
i
feels that the rain is falling vertically down along −
j
. If he doubles his speed,he finds that the rain is coming at an angle θ with the vertical. The velocity of the rain with respect to the ground i
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
Answer:
b is the correct answer