Newton's first law of motion is that an object in motion will tend to stay in motion unless an external force acts upon it.
Consider a long train moving at speed v. Now consider a passenger throwing a ball inside this train, towards the back of the train, with same velocity v (but in the opposite direction of the train movement).
- A passenger inside the train will see the ball moving with speed v
- For an observer outside the train, however, the ball will appear as still. In fact, for him the ball will have a speed v (given by the movement of the train) -v (velocity of the ball but moving in the opposite direction), so the net velocity will be v+(-v)=0.
The apparent magnitude scale is a classification scheme which is based on the brightness of stars. The range of brightness values is from 1 to 6.
The stars which are the most brightest are ranked as number 1 and also called first magnitude stars, stars which are little dimmer than number 1 are ranked as number 2 and also called second magnitude stars. Similarly the most faintest stars are ranked number 6 and also called as the sixth magnitude stars.
Answer:
Explanation:
A polarizer changes the orientation of the oscillations of a light wave.
I₀ = Intensity of unpolarized light = 10
θ = Angle given to the polarizer = 60°
Intensity of light
I = I₀cos²θ
⇒I = 10cos²60
So, the after passing through the second polarizer is 
Answer:
the box has vertical force on the table
Explanation:
There can be no single isolated force, for every action there must be a force of reaction of ingual magnitude and direction, but in the opposite direction
