The question is missing a diagram of the ray reflection. I attached a diagram which comes from a similar question in the answer section. The full question should be as follows:
Two plane mirrors intersect at right angles. A laser beam strikes the first of them at a point d = 10.0cmfrom their point of intersection, as shown in the figure. For what angle of incidence at the first mirror will this ray strike the midpoint of the second mirror (which is s=29.0cm long) after reflecting from the first mirror?
Answer:
34.6°
Explanation:
To strike the midpoint of the second mirror, the ray light will have to travel half of the distance vertically
i.e. 29/2 = 14.5
We can solve this through trigonometry.
Let the angle between the ray and the vertical plane mirror is known as α
tan α = 10/14.5
α = 
= 34.6°
The angle of incidence is the angle between the ray and the normal line of the mirror.
Let angle of incidence of first mirror be β
β = α = 34.6
Answer:
B. chemical only.
Explanation:
In the process of respiration which is a chemical process where organic compound is released. In this process exergonic reaction takes place in which compound changes into different ones.
Following are the two types of respiration:-
1] Aerobic respiration:- In this type of respiration requirement of oxygen is more and energy released is more.
2] Anaerobic respiration:- In this type of respiration oxygen requirement is less and energy released is also less.
Answer:
The average force exerted on the window due to two snowballs is 6 N
Explanation:
Given:
Mass of snowballs 
Kg
Velocity of snowball 
For finding the average force,
Force is equal to the change in momentum,
Here, final velocity is zero so we write,
Where 
sec
N
Above value of force is due to one ball, but here given in question there are two ball,
N
Therefore, the average force exerted on the window due to two snowballs is 6 N
Option B is the correct answer.
MKS system gives the following units:
Distance ----- meters
Mass ----- Kilograms
Time ----- seconds
meter is basic unit for length measurement. smaller units are centimeter, millimeter, micrometer, bigger units are kilometer and so on.
kilogram is the basic unit for mass. smaller unit is gram.
second is the basic unit for time. Greater units are minutes, hours, smallest unit are micro second and so on.
