The process of flask becoming cold is due to endothermic reaction.
Answer: Option B
<u>Explanation:</u>
So two kinds of heat transfer can be possible in any chemical reaction. If the sample is considered as system and the sample container is considered as the surrounding, then heat transfer can occur between them.
If the heat is transferred from the surrounding to the system , then it is an endothermic reaction. And in those cases, the sample holder will be becoming colder. This is because the heat from the surrounding that is the container will be utilized to complete the reaction.
While when there is transfer of heat from the system to surrounding , it will be exothermic reaction and the beaker will be getting hot in this process. So in the present case, the container is becoming cold because of occurrence of endothermic process.
Answer:
Fusion
Fission
Explanation:
The first problem describes a nuclear fusion process. In this process;
- small atomic nuclei combines to form a larger one.
- it is accompanied by a large release of energy
- this energy provides the needed temperature to set up another light nuclei to fuse.
The second problem describes nuclear fission,
- a heavy nuclide is bombarded with a neutron.
- the product formed becomes unstable and subsequently breaks down.
- This leads to a series of chain reactions until stability is attained.
Speed of the roller coaster at the top of the loop= 7.67 m/s
Explanation:
using the law of conservation of energy
KEi + PEi= KEf + PEf
KEi= kinetic energy at the top of the hill=0 because the car is at rest there.
PEi= potential energy at the top of the hill
PEf= potential energy at the top of the loop
KEf= kinetic energy at the top of the loop
Also kinetic energy= 1/ 2m v² and potential energy= mgh
m= mass
h= height
v= velocity
so 0+ mghi = 1/2mv² + mg h
500 (9.8)(10)+ 1/2 (500) v²= 500 ( 9.8) (7)
49000+250 v²= 34300
250v²= 14700
v²=58.8
v=7.67 m/s
Answer: (b)
Explanation:
Given
Mass of box 
Applied force 
Friction force 
Box travels a distance of 
time taken 
Net unbalanced force 
Work done by the unbalanced force
Power developed by unbalanced force
Thus, option (b) is correct.
