Answer:
D
Explanation:
Telescopes detect electromagnetic waves from space and it travels back to the telescope lens in order for you to see.
Answer:
B. They usually need to be cooled to dissipate thermal energy build-up and prevent damage.
Explanation:
High energy mechanical devices needs to be cooled down because they have moving parts which creates heat which may affect the other electrical and electronic component of the device. Because quality of material changes with the temperature. If high temperature occur might change the shape of that component and may affect the efficiency of the machine.
Answer:
469.6KJ
Explanation:
Heat energy required can be calculated using the formula
H = mc∆t where
m is the mass of the water
c is the specific heat capacity of the water
∆t is the change in temperature of the water
Given m = 9.78kg
c = 4186j/kg-c.
∆t = 52.07°C - 40.82°C
∆t = 11.25°C
H = 9.78 × 4186 × 11.25
H = 460,564.65Joules
= 460.6KJ
I did chocolate
1- 1:02
2-47 secs
3- 17 secs
Hope I helped ;)
