Velocity and kinetic energy of moving block

AI Thread Summary
To determine the speed of a 10 kg block subjected to vertical forces of 50N each and horizontal forces of 20N and 50N after 5 seconds, calculate the resultant horizontal force using Newton's second law. Assuming the block starts from rest, apply the formula for acceleration to find the final velocity after 5 seconds. The kinetic energy can then be calculated using the equation KE = 0.5 * mass * velocity^2. The discussion emphasizes the importance of understanding resultant forces and the application of fundamental physics equations. This approach will yield both the block's final speed and its kinetic energy.
lbcc
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Originally Posted by lbcc
okay,
so there's a 10 kg block with four different forces acting upon it:
vertical forces of 50N each
and horizontal forces of 20N and 50N.

After 5 seconds, how fast is this block moving?
and what is the Kinetic Energy of the block after 5 seconds?

if you could give me the equations I would use to figure these out that would be great..
 
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Ok, you have two horizontal forces (I guess they point in opposite directions). From that you can get the resultant force and then use Newtons 2nd law. Knowing initial velocity (I assume the block starts at rest) and the time you can find out the final velocity. And surely you know the equation for kinetic energy?
 
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