A motorbike accelerates with a force of 15000N. It experiences air resistance which acts in the opposite direction with a magnitude of 1200N. Calculate the unbalanced force that is acting on the motorbike.

Ft = 13800 [N]

Explanation:

We have to carry out a force analysis and assume the directions of those forces. First the force that causes the movement of the rider is equal to 15000 [N] and is directed to the right. Since the resistance of the air is opposite to the movement, it generates a resistance with a value of 1200 [N], with direction to the left. However, the rider continues to move to the right, as the force generated by the bike is greater, i.e. this force must be to the right for movement to exist. By means of a summation of forces on the X axis we can calculate the value of the resulting force. The forces to the right will be taken with a positive sign and the forces to the left with a negative sign.

15000 - 1200 = Ft

where:

Ft = unbalanced force [N]

Ft = 13800 [N]

no. dot product   =0 when vecs at right angles

which piece of furniture will have the most inertia and give the furniture movers the most difficulty in moving?  

answer

a 75kg dining table