Momentum = mass x velocity
Before collision
Momentum 1 = 2 kg x 20 m /s = 40 kg x m/s
Momentum 2 = 3 kg x -10m/s = -30 kg x m/s
After collision
Momentum 1 = 2 kg x -5 m/s = -10 m/s
Momentum 2 = 3 kg x V2 = 3V2
Total momentum before = total momentum after
40 + -30 = -10 + 3V2
V2 = <span>6.67 m/s
Total kinetic energy before
</span><span>= (1/2) [ 2 kg * 20 m/s * 2 + 3 kg * ( -10 m/s) *2 ]
= 550 J
</span>
<span>Total kinetic energy after
</span>= (1/2) [ 2 kg * ( - 5 m/s) * 2 + 3 kg * 6.67 m/s *2 ]
= 91.73 J
Total kinetic energy lost during collision
=<span>550 J - 91.73 J
= 458.27 J</span>
Answer: Torque= tangential force × radius of the pulley
Explanation:
Pulley is a simple machine which helps us to lift loads by applying the force in a convenient direction. It consists of a grooved wheel which is free to rotate about an axle passing through the center of the pulley.
For a pulley, the torque 
tangential force × radius of the pulley
Pulleys can be used in combination also to achieve a desired output.
Answer:
Argument in favor of less total energy consumption if the store is kept at a low temperature
Explanation:
Have in mind that if the store has numerous refrigerators and freezers, the energy consumption of those machines have to be included into the analysis.
Recall that the efficiency (or Coefficient Of Performance - COP) of a frezzer or refrigerator is inversely proportional to the temperature difference between the inside of th machine and the environment where it is operation, therefore the smaller the difference, the highest their efficiency. Therefore, the cooler the environment (the temperature at which the store is kept) the better performance of the running refrigerators and freezers.
I - ok. Czechoslovakia is officially taken.
Answer:
Explanation:
T = 2π√(L/g)
If you increase L to 2L, the period is increased by a factor of √2
T = 3.5√2 ≈ 4.9 s
