Yes, the answer is in fact C. All of the above.
Variable stars are stars that change in brightness. The change could be due to the physical change in the star or it could also be caused when another star crosses another, or in other words eclipse.
Explanation:
It is given that a particle covers 10m in first 5s and 10m in next 3s. so using the equation of motion
Case I
s=ut+
2
1
at
2
10=5u+
2
1
a(5)
2
20=10u+25a
4=2u+5a..............(1)
Case 2
In next 3s the particle covers more 10m distance. So
20=8u+
2
1
a(8)
2
5=2u+8a.........(2)
On solving equation (1) and (2)
4=2u+5a
5=2u+8a
a=
3
1
m/s
2
Put the value of a in equation (1)
u=
6
7
m/s
Now to find distance in next 10 s. total time will be 10s
s=
6
7
×10+
2
1
×
3
1
×(10)
2
s=28.33m
Distance travelled in next 2 sec
s=28.33−20=8.33m
Answer:
9000 J
Explanation:
Convert minutes to seconds.
2 min = 120 s
Power = energy / time
75 W = E / 120 s
E = 9000 J
Answer: 83.3 W
Explanation: I think, I’m not sure. If I’m wrong correct me ;)