"Reflection" is the change direction of waves when blocked by obstacle
Answer:
A. 20 m/s north
Explanation:
The velocity of the car can be calculated as:
where
d is the displacement
t is the time interval
Taking north as positive direction, the initial position of the car is
(south)
while the final position is
(north)
So, the displacement is
(north)
The time interval for the motion is
t = 15 s
So, the velocity of the car is
(north)
Answer:
it goes up until we help it to but the moment we stop support it gets affected by gravity and goes back
Explanation:
Answer:
Explanation:
Here image distance is fixed .
In the first case if v be image distance
1 / v - 1 / -25 = 1 / .05
1 / v = 1 / .05 - 1 / 25
= 20 - .04 = 19.96
v = .0501 m = 5.01 cm
In the second case
u = 4 ,
1 / v - 1 / - 4 = 1 / .05
1 / v = 20 - 1 / 4 = 19.75
v = .0506 = 5.06 cm
So lens must be moved forward by 5.06 - 5.01 = .05 cm ( away from film )