It is D. An object can acquire a net charge only when charges are transferred to or from it.
Answer: The poker stick should have low thermal conductivity and high specific heat.
Explanation: For a poker stick that is non flammable, it should have some properties which will not let it heat up faster.
Two properties that satisfy the poker stick are:
- Specific heat
- Thermal conductivity
Specific heat is defined as the amount of heat require to raise the temperature of a mass M by 1 °C. More the specific heat, more amount of heat will be required to raise the temperature of a substance.
Thermal conductivity is defined as the ability of a substance to conduct heat. More thermal conductivity means that the substance will get hot faster as it will conduct more amount of heat.
So, for a substance that should not conduct more heat like the poker stick must have high specific heat and low thermal conductivity.
Hi!
Although all of them might be a good answer the correct has to be <span>C. beliefs and behaviors </span>
Answer:
Explanation:
a )
one kg of coal gives energy of 27 x 10⁶ J
75 kg of coal gives energy of 27 x 10⁶ x 75 J
So rate which energy is coming out of coal per second
= 27 x 10⁶ x 75 J
= 2025 x 10⁶ J /s
2025 million watts .
b ) energy output = 800 million watts
efficiency = (800 / 2025) x 100
= 39.5 % .
Answer:
13.7m
Explanation:
Since there's no external force acting on the astronaut or the satellite, the momentum must be conserved before and after the push. Since both are at rest before, momentum is 0.
After the push
Where 
is the mass of the astronaut, 
is the mass of the satellite, 
is the speed of the satellite. We can calculate the speed 
of the astronaut:
So the astronaut has a opposite direction with the satellite motion, which is further away from the shuttle. Since it takes 7.5 s for the astronaut to make contact with the shuttle, the distance would be
d = vt = 1.83 * 7.5 = 13.7 m
