Is Force Definable with Given Velocity, Time, and Displacement Data?

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Can we define force if ...

Homework Statement


Can we define force if a body from high of ##h_1=4m## goes down to ##h_2=−3m##, for time ##t=4s##, and with velocity of ##v=10\frac{m}{s}##. The acceleration would be ##a=\frac{v}{t}=\frac{10\frac{m}{s}}{4s}=2.5 \frac{m}{s^2}.## Can we define the force using these things? If yes, let me know the formula, if no, let me know :)

Homework Equations


none

The Attempt at a Solution


none.
 
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F = ma, you need the mass as well as acceleration to find the force
 


I know ##F=ma##, but, I have the acceleration, but I don't want mass, I want to know if there's a way to find the Force with distance between two highs , with a velocity for a set time.
 


-Physician said:
Can we define force if a body from high of ##h_1=4m## goes down to ##h_2=−3m##, for time ##t=4s##, and with velocity of ##v=10\frac{m}{s}##. The acceleration would be ##a=\frac{v}{t}=\frac{10\frac{m}{s}}{4s}=2.5 \frac{m}{s^2}.##
This kinematic data doesn't seem consistent. Did you just make it up?
Can we define the force using these things?
No.
 


Yeah, I made it my self, And I see you can't because ##m ,m , s, \frac{m}{s}## wouldn't be able to make ##N## (Newton) or ##kg\frac{m}{s^2}## which is ##kg\frac{m}{s^2}=N##
 


-Physician said:

Homework Statement


Can we define force if a body from high of ##h_1=4m## goes down to ##h_2=−3m##, for time ##t=4s##, and with velocity of ##v=10\frac{m}{s}##. The acceleration would be ##a=\frac{v}{t}=\frac{10\frac{m}{s}}{4s}=2.5 \frac{m}{s^2}.## Can we define the force using these things? If yes, let me know the formula, if no, let me know :)


Homework Equations


none


The Attempt at a Solution


none.

Way too many errors in it.
Firstly you say that object goes from
h1=4m goes down to h2=−3m ?

How can you say that distance will be -3m ? Distance is scalar !
Secondly , yes we can define displacement to be negative with reference to direction but here body is falling uni-directionally. You have to say that body is falling from distance of 4m to 3m.

Again another error : If body is falling downwards then acceleration will be 9.8 or 10m/s2 i.e constant value. This further implies that the velocity of body will keep on increasing by 9.8 or 10m/s , every second. You just can't say that velocity of body will be uniform here in this case.

Again acceleration is rate of change in velocity , not velocity by time.
And lastly , out of curiosity : Are you assuming another planet where acceleration is 2.5m/s2 ?:biggrin:

You CANNOT define FORCE without using or taking MASS of object in ACCOUNT.