Question

a 10 kg block is at rest C constant force F acts on the block along x- axis ,At time To=2 secs ,the block moves 8m.Find F​

Answer 1

The force is F = 40[N]

Step-by-step explanation:

This problem can be solve using the following kinematic equation, in order to find the acceleration.

x = final position = 8 [m]

xo = initial position = 0 [m] "from the rest"

vo = initial velocity = 0 [m/s] "starting from the rest"

a = acceleration [m/s^2]

t = time = 2[s]

`x = x_(o) + v_(o)*t+0.5*a*t^(2)   \\8 = 0.5*a*(2)^(2) \\a = (8)/(0.5*2^(2) ) \\a=4 [m/s^2]`

Now using the second law of Newton, we can find the force exerted. We make the sum of forces equal to the product of the mass by the acceleration.

`F = m*a\\where:\\F =force [N]\\m = mass = 10[kg]\\a = acceleration = 4 [m/s^2]\\\\therefore\\F = 10*4\\F= 40 [N]`