Why is it that force= mass x acceleration and not force=weight x acceleration?

Question

Why is it that force= mass x acceleration and not force=weight x acceleration?

Answer 1

Simply because WEIGHT depends on gravity.

while MASS is constant.

Answer 2

Essentially they are the same. It is when you get farther away from the pull of gravity when mass becomes important.

Answer 3

Mass is the amount of matter present in a body and is an intrinsic property of the body. Mass of an object remains the same always at any place.

Weight on the other hand is the force which a given mass feels due to the gravity at its place. Weight is measured in units of Force like Newton (which is the SI unit of Force).

If your mass is 60 kgs then your weight is approximately 60 x 10 = 600 Newtons. This is because

Force = mass x acceleration (From Newton's second Law)

Thus, weight = mass x acceleration due to gravity

If you go to moon your mass remains same, i.e 60 kgs, but your weight becomes less by 1/6 amount, since moon's gravity is 1/6 that of earth.

Answer 4

Weight IS equal to mass and acceleration but "acceleration due to gravity"...

        In Physics, Mass and Weight are two different terms! Mass is the quantity of matter in a body while Weight (in physics) is the Force with which the earth attracts a body towards its centre!!!

    [ Newton discovered that when two bodies of different masses are thrown downwards from some high place, both the bodies reach the Earth at the same time and with the same acceleration of 9.8 m/s square].......    As the Earth attracts a body( every body has some MASS ) towards its centre through GRAVITATIONAL force, weight is equal to the product of Mass and acceleration due to gravity!!! w= mg

Answer 5

Mass is the amount of substance in a body and is constant

The weight (W) of a body is dependant on its mass  (M) and the accelleration due to gravity (G)

M = W/G

Thus W = M x G

As can be seen from the above the weight of a body depends upon the force due to gravity

Thus the weight of a body will vary according to its location

i.e. A body wieghing 60 Kg on Earth will weigh 10 Kg on the moon

Answer 6

Er, easy really, in that "weight" depends upon local gravitaional force, whereas mass is a constant value, no matter where you are.

So a simple answer !

Bob

Answer 7

Weight itself is a force where the accelaration multiplied to mass is g i.e. accn due to gravity.

Answer 8

Mass and weight are totally different. Weight confides with gravity, and thus it doesn't work everywhere else. But mass is- it is a constant.

Unless you exercise- then it decreases. Haha.

Answer 9

weight is the amount gravity affects you and that is in newtons but mass is how much you are e.g. ..stone or ..kg or ..g

Answer 10

Mass

The mass of an object is the measure of the amount of matter in it. Mass should not be confused with weight.

Weight

The weight of an object depends upon the force of gravity on it. Hence weight, unlike mass, is not constant and would differ on the moon and on the earth.

weight = mass * gravitational force

W = m * g

Answer 11

Weight is defined as the gravitational force that is exerted on a mass. Mass is how heavy the object is without the force of gravity acting upon it. So, it would not make sense for force = force * acceleration or more exactly force = weight * acceleration.

Answer 12

It is because weight of a body equals its MASS multiplied to the (acc. due to gravity) or the gravitational force.

So whenever a body is situated in a Gravitational field its Mass is considered only , so as to make the problems in Mechanics somewhat easy. And so "Mass X Acceleration" gives the effective force acting in the push or pull direction of the applied force.

Answer 13

do ur own homework!

Answer 14

weight essentially is force!

Weight = mass x acceleration due to gravity

Answer 15

i was never too good at physics. but i think mass includes gravity or something. so your weight in space is the same on earth. but your mass changes.

Answer 16

because weight = mass x gravity, and gravity is not part of the expression