Answer:
Velocity and speed both are continuously increasing.
Acceleration is constant.
Explanation:
Speed is defined as length of path covered by a body per unit time. Speed is a scalar quantity that consist of magnitude only and not direction.
Velocity is defined as the displacement per unit times. Displacement is the shortest distance between the two points. It is a vector quantity and hence has a direction in the direction of displacement along with its own magnitude.
- Both velocity and speed have same unit of measure which is meter per second in S.I. During <em>free fall</em> in the absence of any air resistance the velocity and speed both will be having a vertical downward direction with continuously increasing magnitude. Tough we are not concerned about the direction when discussing about speed but here both are equal since the motion is linear.
Acceleration is the rate of change in velocity of a body which is a vector quantity. For speed we are concerned about instantaneous acceleration since for a short period of time it may have a specific direction.
- During free fall the acceleration is of a body is equal to the acceleration due to gravity and constant when the height of fall is much lesser than the radius of the earth.
Answer:
Thus, the change in the weight of the person is 1.6N , option c is correct.
Explanation:
Answer: Option (A) is the correct answer.
Explanation:
Laser helps in zooming an image on which it is directed or falls so that it becomes easier for a large population to understand what the teacher or guide is talking about.
For example, when Greg is giving slide show presentation to a large audience then in order to make his slides visualized by everyone in the room he uses laser.
Therefore, we can conclude that a laser best help him with the presentation as he can use the laser to enlarge images on the slides.
Answer:
U = - G m M / r
Explanation:
The gravitational potential energy is given by the expression
U = - G m₁ m₂ / r
dodne G is the gravitational cosntnate (G = 6.67 10⁻¹¹¹), m and m are the mass of the bodies involved
subtype the given values
U = - G m M / r
Answer:
increasing the temperature of the rod
Explanation:
Sound wave is a longitudinal wave and its speed in a solid rod is given by the formula

here we know that
Y = young's modulus
= density of the medium
so as we increase the temperature of rod the density of the rod will decrease while the elasticity will remain same
So on increasing the temperature we can say that speed will increase due to decrease in the density