answer my question please
Answers
Answer: MARK IT BRAINLIEST PLZZZ
Explanation:
Q 15.) Conduction is the transfer of thermal energy through direct contact. Eg: A pan warming on a stove is an example.Radiation is the transfer of thermal energy through thermal emission. Eg :Waves produced by mobile phones.
Q16.)<A> no. of oscillations= 40
time taken= 4seconds.
time period= time taken for no. of oscillations/ no. of oscillations.
time period for this condition is= 4/40
=1/10th of 1 second.
<B> I don't know the answer. Srry
Answer:
15. Conduction:-
- Conduction is the transfer of heat energy by direct contact. Whenever two objects are in direct contact with one another, there will be a transfer of heat from the hotter object to the colder one, which is due to conduction. Further, the objects which permit heat to travel easily through them are called conductors.
- Example:- An ice cube will soon melt if you hold it in your hand. The heat is being conducted from your hand into the ice cube
Radiation:-
- Radiation is the transfer of energy with the help of electromagnetic waves. The heat transfer mechanism in which no medium is required is called radiation. It refers to the movement of heat in waves, as it does not need molecules to travel through. The object need not be in direct contact with one another to transmit heat. Whenever you feel heat without actually touching the object, it is because of radiation. Moreover, colour, surface orientation, etc. are some of the surface properties on which radiation depends greatly.
- Examples :- To heat food in a microwave oven, high levels of radiation are employed.
16. i) time period of a pendulum = time taken ÷ number of oscillations
= 4 ÷ 40
= 0.1
the time period of the given pendulum = 0.1 sec
ii) 120km/hr
1 hr = 60 min
30 min = 60 ÷ 2
distance traveled = 120 ÷ 2
= 60km
The car has covered a distance of about 6km.
(pls mark me as brainliest)