Answer:
This does not violate the conservation of energy.
Explanation:
This does not violate the conservation of energy because the hot body gives energy in the form of heat to the colder body, this second absorbs energy. This will be the case until both bodies reach the same temperature, reaching thermal equilibrium and reducing the transfer of thermal energy. In this way the energy was only transferred from one body to another but the total energy of the system (body 1 plus body 2) will be the same as in the beginning, respecting the principle of conservation of energy or also called the first principle of thermodynamics .
The part of physics that studies these processes is in turn called heat transfer or heat transfer or thermal transfer. Heat transfer occurs whenever there is a thermal gradient or when two systems with different temperatures come into contact. The process persists until thermal equilibrium is reached, that is, until temperatures are equalized. When there is a temperature difference between two objects or regions close enough, the heat transfer cannot be stopped, it can only be slowed down.
Answer:
Few millimeter thick aluminium, water, wood, acrylic glass or plastic.
Explanation:
The materials that are best for protection against beta particles are few millimeter thickness of aluminium, but for the high energy beta-particles radiations the low atomic mass materials such as plastic, wood, water and acrylic glass can be used.
These materials can also be used in personal protective equipment which includes all the clothing that can be worn to prevent any injury or illness due to the exposure to radiation.
Answer : The mass of ice melted can be, 3.98 grams.
Explanation :
First we have to calculate the moles of ice.
where,
Q = energy absorbed = 27.2 kJ
= enthalpy of fusion of ice = 6.01 kJ/mol
n = moles = ?
Now put all the given values in the above expression, we get:
Now we have to calculate the mass of ice.
Molar mass of ice = 18.02 g/mol
Thus, the mass of ice melted can be, 3.98 grams.
Answer:
e. Only the rocket's motion from the top of its flight path until just before landing is free-fall.
Explanation:
A free-fall is a fall just under force of gravity. The rocket;s upward motion is result of engine push - even if it was shut down - and rocket free of engine push effect when it reaches it's maximum height after shutting down of engine. Then rockets stops at it's maximum height for a moment and rtuens back as free fall with only force of gravitation pulling it back to ground with acceleration 'g'.
