Answer:

Explanation:
information we know:
Total force: 
Weight: 
distance: 
vertical component of the force: 
-------------
In this case we need the formulas to calculate the components of the force (because to calculate the work we need the horizontal component of the force).
horizontal component: 
vertical component: 
but from the given information we know that 
so, equation these two
and 

and we know the force
, thus:

now we clear for 

the angle to the horizontal is 15.466°, with this information we can calculate the horizontal component of the force:


whith this horizontal component we calculate the work to move the crate a distance of 4 m:

the work done is W=173.48J
Answer:
90 hp
Explanation:
Power = work / time
P = ½ (1500 kg) (25 m/s)² / 7.0 s
P = 67,000 W
P = 90 hp
Answer:
a) 0.147 N
b) 9.408 N
c) 9.261 N
Explanation:
The tension on the cord is the only force keeping the block in circular motion, thus representing the entirety of its centripetal force
. Plugging in values for initial and final states and we get answers for a and b. The work done by the person causes the centripetal force to increase, and thus is the difference between the final tension and the initial tension.
Answer:
M= F^n / a+g
Explanation:
This shows correctly Newton’s second law, where sum of forces is divided by mass is equal to acceleration. Also mass can’t be negative so F^n is positive.
A
Excitation to a higher energy state requires energy which is absorbed from the electromagnetic waves applied.