- #1
BunDa4Th
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Okay I am confuse on how i came to this conclusion and how i came to that answer.
A block of mass 2.50 kg is pushed 2.80 m along a frictionless horizontal table by a constant 12.0 N force directed 25.0° below the horizontal.
(a) Determine the work done by the applied force.
30.45J
(b) Determine the work done by the normal force exerted by the table.
0 J
(c) Determine the work done by the force of gravity.
0J
(d) Determine the work done by the net force on the block.
30.45J
I am confuse on b, c, d. I know that to determine the applied force i would use W = (Fcostheta)(deltaX).
For b i would use W = (mgcos90)deltaX is that correct? because since the block is on a table which is flat and normal force is pointing up so from table to normal force it makes a 90 degree angle.
For c I did a guess since I was not sure but i thought that it would be zero since there is no incline and gravity is not acting on this block because its not falling.
D i came up with Wnet = W_F + W_f + W_N + W_mg
W_F = 30.45
W_f = 0 (no friction so it is zero)
W_N = 0 (not sure why)
W_mg = 0 (not sure why)
sorry its a bit long but can anyone explain this to me.
A block of mass 2.50 kg is pushed 2.80 m along a frictionless horizontal table by a constant 12.0 N force directed 25.0° below the horizontal.
(a) Determine the work done by the applied force.
30.45J
(b) Determine the work done by the normal force exerted by the table.
0 J
(c) Determine the work done by the force of gravity.
0J
(d) Determine the work done by the net force on the block.
30.45J
I am confuse on b, c, d. I know that to determine the applied force i would use W = (Fcostheta)(deltaX).
For b i would use W = (mgcos90)deltaX is that correct? because since the block is on a table which is flat and normal force is pointing up so from table to normal force it makes a 90 degree angle.
For c I did a guess since I was not sure but i thought that it would be zero since there is no incline and gravity is not acting on this block because its not falling.
D i came up with Wnet = W_F + W_f + W_N + W_mg
W_F = 30.45
W_f = 0 (no friction so it is zero)
W_N = 0 (not sure why)
W_mg = 0 (not sure why)
sorry its a bit long but can anyone explain this to me.