Question

A block is pulled across a table by a constant force of 9.20 N. If the mass of the block is 2.30kg, how fast will the block be moving after 2.00 seconds? Assume negligible friction.

Answer 1

`8\:\text{m/s}`

Step-by-step explanation:

From Newton's 2nd Law, we have
`\Sigma F=ma`. Using this, we can find the acceleration of the object:

`9.20=2.30a,\\a=(9.20)/(2.30)=4\:\mathrm{m/s^2}`.

Now that we've found the block's acceleration, we can use the following kinematics equation to find its final velocity after 2 seconds:

`v_f=v_i+at,\\v_f=0+4(2),\\v_f=\boxed{8\:\text{m/s}}`

*Assumption: The block is initially at rest and has a initial velocity of zero. Otherwise, the question is unsolvable.