Answer:
Heat flows from hot to cold objects. When a hot and a cold body are in thermal contact, they exchange heat energy until they reach thermal equilibrium, with the hot body cooling down and the cold body warming up. This is a natural phenomenon we experience all the time.
Explanation:
Answer:
I should be active for 15 hours to meet the physical activity requirement.
Explanation:
Since time dilates in moving objects, we use the formula t = t₀/√(1 - β²) where t = time in space vehicle, t₀ = time on earth = 9 hours and β = v/c where v = speed of space vehicle = 0.8c.
So, t = t₀/√(1 - β²)
t = 9/√(1 - (v/c)²)
= 9/√(1 - (0.8c/c)²)
= 9/√(1 - (0.8)²)
= 9/√(1 - (0.64)
= 9/√0.36
= 9/0.6
= 15 hr
So, according to a timer on the space vehicle, I should be active for 15 hours to meet the physical activity requirement.
Answer:
The pressure exerted by the brick on the table is 18,933.3 N/m².
Explanation:
Given;
height of the brick, h = 0.1 m
density of the brick, ρ = 19,300 kg/m³
acceleration due to gravity, g = 9.81 m/s²
The pressure exerted by the brick on the table is calculated as;
P = ρgh
P = (19,300)(9.81)(0.1)
P = 18,933.3 N/m²
Therefore, the pressure exerted by the brick on the table is 18,933.3 N/m².
Explanation:
Nuclear reactions are the reactions in which nucleus of an atom changes either by splitting or joining with the nucleus of another atom.
There are two types of nuclear reactions.
- Nuclear fission - In this process, large atomic nuclei splits into smaller nuclei.
- Nuclear fusion - In this process, two small nuclei combine together to form a large nuclei.
Both nuclear fission and fusion processes involve nuclei of atoms.
For example, 
Thus, we can conclude that statements which are true are as follows.
- Nuclear reactions involve the nuclei of atoms.
- The products of nuclear reactions are lighter than the reactants.
Answer:
Explanation:
1) True. The stored energy (U) is proportional to the electric field strength (E). The electric field strength decreases when a dielectric is introduced hence inserting a dielectric decreases U.
2) False. From the formula
, capacitance is inversely proportional to distance hence if the distance is doubled, capacitance decreases.
3) False. As the distance between the electric field and the object increases, its electric field decreases.
4) False. If a dielectric is inserted, the plates are further separated. Q stays the same.
5) True. The electric field strength decreases when a dielectric is introduced and capacitance is inversely proportional to electric field hence Inserting a dielectric increases C
6) True. If a dielectric is inserted, the plates are further separated. Q stays the same.
7) True. When the distance is doubled, U increases