Answer:
D) Fusion requires high temperatures and pressures, so how have they reduced the energy cost for it?
Explanation:
Fusion requires high temperatures and pressure for initiation of reaction . There is no chain reaction in it so there is no problem of controlling the problem . On the other hand , the reaction tends to stop as soon as temperature goes down due to heat getting dissipated . There is no problem of fuel as its fuel is deuterium which is present in nature in large amount . The question which is pertinent is that the cost involved in attaining so high temperature is very high so is it cost effective to produce energy by incurring so much of cost . Producing energy by using so much of energy in the beginning appears to be preposterous.
Answer:
63.3 KJ
Explanation:
Quantity of heat lost to the skin = mLw + mcΔT
where is mass in kg, Lw is latent heat of vaporization in KJ/kg ( 2.256 × 10^6 KJ/Kg), c is specific heat capacity of water (4190 J/(Kg.K) and ΔT is the change in temperature
m = 25g = 25 /1000 = 0.025 kg
quantity of heat loss = (0.025 × 2.256 × 10^6) + ( 0.025 × 4190 × (100 -34 )
Quantity of heat loss to the skin = (5.64 × 10^4) + 5530.8 = 56400 + 6913.5 = 63313.5 = 63.3 KJ
A. The initial speed in which the ball should be thrown is 27.65 m/s
B. The total time spent by the ball in the air is 5.64 s.
A. Determination of the initial velocity
- Maximum height (h) = 39 m
- Final velocity (v) = 0 m/s
- Acceleration due to gravity (g) = 9.8 m/s²
v² = u² – 2gh (since the ball is going against gravity)
0² = u² – (2 × 9.8 × 39)
0 = u² – 764.4
Collect like terms
u² = 0 + 764.4
u² = 764.4
Take the square root of both side
u = √764.4
u = 27.65 m/s
B. Determination of the total time spent by the ball in the air.
We'll begin by calculating the time taken to reach the maximum height.
- Maximum height (h) = 39 m
- Initial velocity (u) = 27.65 m/s
- Final velocity (v) = 0 m/s
- Time to reach maximum height (t) =?
s = ½(u + v)t
39 = ½(27.65 + 0)t
39 = ½ × 27.6 × t
39 = 13.825 × t
Divide both side by 13.825
t = 39 / 13.825
t = 2.82 s
Finally, we shall determine the total time.
- Time to reach maximum height (t) = 2.82 s.
- Total time in the air (T) =?
T = 2t
T = 2 × 2.82
T = 5.64 s
Therefore, the total time spent by the ball in the air is 5.64 s
Learn more about projectile motion: brainly.com/question/15824795
Answer:
a. The moment of the 4 N force is 16 N·m clockwise
b. The moment of the 6 N force is 12 N·m anticlockwise
Explanation:
In the figure, we have;
The distance from the point 'O', to the 6 N force = 2 m
The position of the 6 N force relative to the point 'O' = To the left of 'O'
The distance from the point 'O', to the 4 N force = 4 m
The position of the 4 N force relative to the point 'O' = To the right of 'O'
a. The moment of a force about a point, M = The force, F × The perpendicular distance of the force from the point
a. The moment of the 4 N force = 4 N × 4 m = 16 N·m clockwise
b. The moment of the 6 N force = 6 N × 2 m = 12 N·m anticlockwise.
U have to *modify it to increase its ground clearance*