Question

I have some doubts in Science. Answer them in simplest words. Please don't copy answers.

Answer 1

velocity it is displacement per unit time
vector it has both magnitude and directions
scaler it has only magnitude
acceleration is the rate of change of velocity

Answer 2

1.) (i) Velocity is the displacement travelled by a body in unit time.
Velocity = Displacement/time

(ii)Frequency is the oscillations or vibration made by any particle in 1 sec.

(iii)Acceleration can be defined as rate of change of velocity.
a = (v-u)/t

(iv)vector quantities are those which have both magnitude and direction.
eg:- velocity, displacement etc.

(v)Quantities which have only magnitude and not direction are called scalar quantities.
eg:- speed, distance etc.

2.)If the mass of an object increases then Force needed must be increased. And we know that F= ma (a=rate of change of velocity). So, it depends on what the mass and force will be to know about a. a can either increase, decrease or it may remain same.

3.)(i) True, because F = ma, so force depends on both mass and a
(ii) True, it just means that force is the product of mass and acceleration and so we can say the a can be equal to force applied on mass or F/m.
(iii) I guess false, because weight of a body is "ma or mg" so its unit can only be Newton or kgm/s square.
(iv)True, it means that mass is just the material present in a body. or it can be said the weight of body without g and without any kind of force applied.