Answer:
Explanation:
Even though the minimum temperature is more than the freezing point, Frost was observed on the ground because the ground will cool rapidly as cool air tends to move towards the ground, the temperature of the ground is lower than the atmosphere a few feet above it.
As the thermometer is kept some feet above the ground so ground temperature may be lower than the minimum recorded temperature.
Answer:
The speed of the Jocko and the ball move after he catches the ball is 0.75 m/s.
Explanation:
Given that,
Mass if Jocko, m = 60 kg
Mass of the ball, m' = 20 kg
Speed of the ball, v = 3 m/s
Let V is the speed of Jocko and the ball move after he catches the ball. The momentum of the system remains conserved. Using the conservation of momentum as :

So, the speed of the Jocko and the ball move after he catches the ball is 0.75 m/s.
Explanation:
It is given that,
The distance between the first spot and the central minimum is, s = 0.007 cm
Length, l = 12 m
Wavelength, 
We need to find the width of the hair. Using the condition of diffraction pattern as :
, d is the width of the hair


d = 0.00102
or

So, the width of the hair is
. Hence, this is the required solution.
Explanation:
Below is an attachment containing the solution.