Answer:
Part a)

Part b)
Ball thrown downwards =
Ball thrown upwards =
Part c)

Explanation:
Part a)
Since both the balls are projected with same speed in opposite directions
So here the time difference is the time for which the ball projected upward will move up and come back at the same point of projection
Afterwards the motion will be same as the first ball which is projected downwards
so here the time difference is given as



Part b)
Since the displacement in y direction for two balls is same as well as the the initial speed is also same so final speed is also same for both the balls
so it is given as




Part c)
Relative speed of two balls is given as


now the distance between two balls in 0.8 s is given as



The answer is 21m because the motion is in one dimension with constant acceleration.
The initial velocity is 0, because it started from rest, the acceleration <span>ax</span> is <span>4.7<span>m<span>s2</span></span></span>, and the time t is <span>3.0s</span>
Plugging in our known values, we have
<span>Δx=<span>(0)</span><span>(3.0s)</span>+<span>12</span><span>(4.7<span>m<span>s2</span></span>)</span><span><span>(3.0s)</span>2</span>=<span>21<span>m</span></span></span>
Answer:
1.3 x 10⁻⁴ m
Explanation:
= wavelength of the light = 450 nm = 450 x 10⁻⁹ m
n = order of the bright fringe = 1
θ = angle = 0.2°
d = separation between the slits
For bright fringe, Using the equation
d Sinθ = n
Inserting the values
d Sin0.2° = (1) (450 x 10⁻⁹)
d (0.003491) = (450 x 10⁻⁹)
d = 1.3 x 10⁻⁴ m
Explanation:
It is given that,
Velocity in East, 
Velocity in North, 
(a) The resultant velocity is given by :

(b) The width of the river is, d = 80 m
Let t is the time taken by the boat to travel shore to shore. So,


t = 16 seconds
(c) Let x is the distance covered by the boat to reach the opposite shore. So,


x = 48 meters
Hence, this is the required solution.
To solve for distance use the formula for distance d = st, or distance equals speed times time.
distance = speed x timeSpeed
so the answer is 240 miles per hour.