Answer:
Interchanging the poles of the magnet
Reversing the direction of the applied current
Explanation:
- The working of the electric motor is associated with Fleming's left-hand rule.
- It states that if a current-carrying conductor is placed inside a magnetic field, it experiences a force in the direction perpendicular to the direction of the electric current and magnetic field.
- These three physical quantities are placed in a mutually perpendicular direction.
- So, in order to reverse the direction of force, you have to either change the direction of the current or magnetic field.
The ball's horizontal and vertical velocities at time 
are
but the ball is thrown horizontally, so 
. Its horizontal and vertical positions at time are
The ball travels 22 m horizontally from where it was thrown, so
from which we find the time it takes for the ball to land on the ground is
When it lands, 
and
Answer:
8, 8 W
Explanation:
The useful power of 1 Light Emitting Diode is
Total power required is 1.6 W
Number of Light Emitting Diodes would be
The number of Light Emitting Diodes is 8.
Power would be
The power that is required to run the Light Emitting Diodes is 8 W
Answer: 2.72 metres
Explanation:
Given that:
frequency of sound F = 123 Hz. wavelength of sound in the air = ?
speed of sound in air V = 334 m/s
Recall that wavelength is the distance covered by the wave after one complete cycle. It is measured in metres, and represented by the symbol λ.
So, apply V = F λ
λ = V /F
λ = 334m/s / 123Hz
λ = 2.72m
Thus, the wavelength of this sound in the air is 2.72 metres
Answer: Satellite technology allows us to monitor and track the changes in the polar ice sheets. This can help us plan and direct conservation efforts for the animals that depend on polar ice in order to survive.
Explanation:
A satellite orbits around Earth. We have different satellites for different purposes. A satellite has transmitter and receiver for sending and receiving information. For the use of environment, only one statement seems correct that is: Satellite technology allows us to monitor and track the changes in the polar ice sheets. This can help us plan and direct conservation efforts for the animals that depend on polar ice in order to survive.
Rest options are true but not from the environment point of view.
We know that animals are dependent on the environment for their survival. polar ice caps are difficult to reach and monitor. For making conservation plan for the animals residing in these remote areas, satellite technology is very crucial.
