Answer:
Change in Velocity because

Explanation:
Remeber area is length times Width. In this case, the area under a accleraton vs time graph is Accleration Times Time. Which is velocity
Answer:
a)15 N
b)12.6 N
Explanation:
Given that
Weight of block (wt)= 21 N
μs = 0.80 and μk = 0.60
We know that
Maximum value of static friction given as
Frs = μs m g = μs .wt
by putting the values
Frs= 0.8 x 21 = 16.8 N
Value of kinetic friction
Frk= μk m g = μk .wt
By putting the values
Frk= 0.6 x 21 = 12.6 N
a)
When T = 15 N
Static friction Frs= 16.8 N
Here the value of static friction is more than tension T .It means that block will not move and the value of friction force will be equal to the tension force.
Friction force = 15 N
b)
When T= 35 N
Here value of tension force is more than maximum value of static friction that is why block will move .We know that when body is in motion then kinetic friction will act on the body.so the value of friction force in this case will be 12.6 N
Friction force = 12.6 N
These are all caused by tectonic plate movements. Some areas of the globe are more susceptible to these disasters because they are on or near a fault line where the Earth’s tectonic plates rub against one another, slip beside and under each other, or collide. The places near fault lines are more likely to see earthquakes, tsunamis, and volcanic activity.
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.