Answer:
A laser is created when the electrons in atoms in special glasses, crystals, or gases absorb energy from an electrical current or another laser and become “excited.” The excited electrons move from a lower-energy orbit to a higher-energy orbit around the atom's nucleus.
Answer:
The ball experiences the greater momentum change
Explanation:
The momentum change of each object is given by:

where
m is the mass of the object
v is the final velocity
u is the initial velocity
Both objects have same mass m and same initial velocity u. So we have:
- For the ball, the final velocity is

Since it bounces back (so, opposite direction --> negative sign) with same speed (so, the magnitude of the final velocity is still u). So the change in momentum is

- For the clay, the final velocity is

since it sticks to the wall. So, the change in momentum is

So we see that the greater momentum change (in magnitude) is experienced by the ball.
Anything that is possibly solid or can be contained in a solid
Mass is the amount of matter that is contained in a certain object.
Like
20 kg
10 g
100 lb
Answer:
Wavelength, 
Frequency, 
Explanation:
We need to find the intensity of the radiation is a maximum for a black body at 298 K. It can be calculated using Wein's displacement law. It is given by :


Here, T = 298 K


If f is the frequency of black body radiation. It is given by :



Hence, this is the required solution.
Answer:

Explanation:
The torque of a force is given by:

where
F is the magnitude of the force
d is the distance between the point of application of the force and the centre of rotation of the system
is the angle between the direction of the force and d
In this problem, we have:
, the force
, the distance of application of the force from the centre (0,0)
, the angle between the direction of the force and a
Therefore, the torque is
