Answer:
The angle of incidence is the angle formed by the incident ray and the perpendicular to the surface. Together, the angle of incidence and the angle the incident ray makes with the surface form a right angle (90 degrees). The angle of incidence is therefore given by the following expression:
Angle of incidence = 90 degrees - angle ray makes with the surface
In your example
Angle of incidence = 90 degrees - 40 degrees = 50 degrees
The law of reflection states that the angle of incidence equals the angle of reflection, which is also measured with respect to the perpendicular to the surface, so
Angle of reflection = Angle of incidence = 50 degrees.
initial height of the Pole - vaulter = 4.2 m
now when he reached the top of the pad his height is 80 cm
so the total displacement of the person will be = 4.2 - 0.8 = 3.4 m
now we can use kinematics to find the speed just before he touch the pad




now when he compressed on pad the distance after which he will stop is 50 cm
so now again using kinematics we can say



so it is acceleration by -66.64 m/s^2
The ratio of (new volume / old volume) is the same as the ratio of (new temperature / old temp).
Just remember that you have to use the ABSOLUTE temperatures.
An absolute temperature is (Celsius + 273).
The main component in a reflecting telescope is a mirror where the light will bounce off and is then focused into a smaller area. In contrast, a refracting telescope uses lenses that focus the light as it travels towards the other end.
Two different types of reflecting telescopes are:
1.Cassegrain reflector
2.Newtonian telescope
Explanation:
- The distinction between the two is in how they manipulate the incoming light in order to magnify the image. The main component in a reflecting telescope is a mirror where the light will bounce off and is then focused into a smaller area.
- Key advantage of reflecting telescopes is how big you can make them. With lenses, the maximum size is limited to about one meter, largely because of the problems stated above as well as the skyrocketing costs.
- The Newtonian telescope, also called the Newtonian reflector, is a type of reflecting telescope invented Sir Isaac Newton, using a concave primary mirror and a flat diagonal secondary mirror. The Newtonian telescope's simple design has made it very popular with amateur telescope makers.
- The Cassegrain reflector is a combination of a primary concave mirror and a secondary convex mirror, often used in optical telescopes and radio antennas, the main characteristic being that the optical path folds back onto itself, relative to the optical system's primary mirror entrance aperture.