Answer:
Explanation:For second hand, period = 1 min = 3660 s; frequency = 0.0166 Hz}\\\mbox{For minute hand, period = 1 hr = 3600 s; frequency = 2.77}\times10^{-4} Hz\\\mbox{For hour hand, period = 12 hrs = 4300 s; frequency = 2.3}\times10^{-5} Hz.
Explanation:
Power = work / time
Power = force × distance / time
P = (650 kg) (10 m/s²) (20 m) / (15 s)
P = 8667 W
Answer:B,C,D
Explanation:
Thermodynamic efficiency is given by

efficiency can be increased by Keeping
constant and increasing 
Keeping
constant and decreasing
by increasing 
by decreasing
ratio
The answer is 0k because 143c equals nothing
Answer:
-20000 kgm/s
Explanation:
Impulse: This can be defined as the product of the mass of a body and its change in velocity. The S.I unit of impulse is kgm/s.
Mathematically, impulse can be expressed as
I = m(v-u).............. Equation 1.
Where I = impulse applied to the car to bring it to rest, m = mass of the car, u = initial velocity of the car, v = final velocity of the car.
Given: m = 1000 kg, u = 20 m/s, v = 0 m/s ( to rest)
Substitute into equation 1
I = 100(0-20)
I = 1000(-20)
I = -20000 kgm/s
Hence the impulse applied to the car to bring it to rest = -20000 kgm/s