Answer:1). Distance of far point x=0.9m
Therefore, since the image is virtual
-f=-x = -0.9m
Power of the concave lenses = 1/f = 1/-0.9
= -1.11D
2 ) near point is 21cm = 0.21m
Power = 4-1/near point
= 4/0.21
= 14.2D.
Answer:
Radius of the solenoid is 0.93 meters.
Explanation:
It is given that,
The magnetic field strength within the solenoid is given by the equation,
, t is time in seconds

The induced electric field outside the solenoid is 1.1 V/m at a distance of 2.0 m from the axis of the solenoid, x = 2 m
The electric field due to changing magnetic field is given by :

x is the distance from the axis of the solenoid
, r is the radius of the solenoid


r = 0.93 meters
So, the radius of the solenoid is 0.93 meters. Hence, this is the required solution.
<u>Answer:</u>
<em>The moon doesn’t change shape on its own.</em>
<u>Explanation:</u>
Shapes of moon that we observe is based on the different perspectives of view from the earth and position of moon with respect to the sun. The changes arise due to the rotation of earth on its own axis as well as the revolution of moon on its orbit. The moon doesn’t have any light of its own.
It just reflects off the light from the sun. Due to tidal locking phenomenon one face of the moon permanently faces the sun. Because of the changes in position of moon with respect to the sun the moon is lighted up variably giving rise to various phases like new moon, full moon, crescent etc.
Answer:
30 miles people hour (mph)
Explanation:
The maximum speed for one flat tyre is 30mph, for both tyres it is 20 mph and for two tyres on the same side it is 30mph. When a tyre is punctured driving at high speed should be avoided and not too long distance should be covered to avoid further accident and for the safety of other vehicles. Speed limit and distance for flat tires should be strictly followed.