Answer:
C. Both a and b
Explanation:
Firstly, persons and objects in a moving plane as described in this question, are moving at the same speed as the plane even if there is no individual movement of these objects.
However, this question describes a person sitting still in a moving plane. This means that;
- The person is motionless in relation to everything in the plane i.e the person is not moving even if other things in the plane are.
- The person is in motion compared to everything on the ground i.e. the person is moving at the same speed as the plane, hence, in comparison with the ground, the person is moving.
Therefore, options A and B are correct
<span>The work output of a machine divided by the work input is the "Efficiency" of the machine.
Hope this helps!</span>
Answer:
(a) convex mirror
(b) virtual and magnified
(c) 23.3 cm
Explanation:
The having mirror is convex mirror.
distance of object, u = - 20 cm
magnification, m = 1.4
(a) As the image is magnified and virtual , so the mirror is convex in nature.
(b) The image is virtual and magnified.
(c) Let the distance of image is v.
Use the formula of magnification.
Use the mirror equation, let the focal length is f.
Radius of curvature, R = 2 f = 2 x 11.67 = 23.3 cm
A supernova is a star that suddenly increases greatly in brightness because of a catastrophic explosion that ejects most of its mass.
Gravitational potential energy is energy.
The unit of energy is the Joule.
1 Joule = 1 kilogram-meter² / sec²
