Which of the following examples are producing negative work upon an object? Select all that apply. a) an upward force is applied to an object to move it downward at a constant speed.
b) an downward force is applied to an upwardmoving object to slow it down as it moves.
c) an upward force is applied to an object to suspend it motionless in mid-air.
d) a force is applied to an object to hold it at rest on a ramp.
e) a rightward force is applied to an object to move it to the right at a constant speed. ​

given data:

determine the horse power (h.p) = ?

force applied to move the box(f) = 10 pounds,

box lifted from a distance         (d) = 3 feet

time taken to lift                         (t) = 10 sec,

the horse power is defined as amount of work required to move a load. the horse power is equal to 550 foot-pound per second

                  1 h.p   = 550 foot-pound/second

it can also be defined as the the load that need to be move a body for certain distance in a certain amount of time.

mathematically,

                      h.p = (force × distance)/ time

                            = (10 × 3)/ 10

                            = 30/10

                            = 3 foot -pound/sec

hence, the horse power is needed to move the box is 3 foot-pound/second

important note: 1 h.p = 550 foot-pound/second = 746 watts