Answer:
Option D - 0.2 s
Explanation:
We are given;
Initial velocity; u = 7 m/s
Height of table; h = 1.8m
Now,since we want to find the time the car spent in the air, we will simply use one of Newton's equation of motion.
Thus;
h = ut + ½gt²
Plugging in the relevant values, we have;
1.8 = 7t + ½(9.8)t²
4.9t² + 7t - 1.8 = 0
Using quadratic formula to find the roots of the equation gives us;
t = -1.65 or 0.22
We can't have negative t value, thus we will pick the positive one.
So, t = 0.22 s
This is approximately 0.2 s
100/2.5 because power=energy/time
Force, the unit is Newton, newton is the force to accelerate a mass. so it should be kg m/s^2
joule (J) is equal to Nm not Ns
the unit of work is J and it is correct.
the unit of power is J/s which is equal to W
the unit of of energy is the same with work, which is J which equivalent to kgm2/s2
Answer:
i hope the answear is D becuase went over this long time ago when i was like you
Explanation:
P=W/t
P=Power
W=Work
t=Time
Convert 16 minutes in seconds:
16 mins = 960 secs
P=6720/960=7.23 W [Watt]
