Answer:
The rate of transfer of heat is 0.119 W
Solution:
As per the question:
Diameter of the fin, D = 0.5 cm = 0.005 m
Length of the fin, l =30 cm = 0.3 m
Base temperature,
Air temperature,
k = 388 W/mK
h =
Now,
Perimeter of the fin, p =
Cross-sectional area of the fin, A =
A =
To calculate the heat transfer rate:
where
Now,
Answer:
The normal force is the force that surfaces exert to prevent solid objects from passing through each other. If the object is at rest, the net force on the object is equal to zero. Therefore, the downward force (weight) must be equal to the upward force (normal force).
The acceleration due to gravity at the Earth's surface is 9.8 m/s/s
<span>So a 2 kg object will accelerate at 9.8 m/s/s if it is dropped..... actually all dropped objects will accelerate at the same rate. </span>
<span>The force of gravity on the object is given by Newton's 2nd Law </span>
<span>F = m . a </span>
<span>F = 2 . 9.8 = 19.6 N </span>
<span>Now go to Mars , with a lower gravitational field strength. It only accelerates falling objects at 3.71 m/s/s </span>
<span>So the force of gravity on the object is F = 2 . 3.71 = 7.42 N </span>
<span>But the answer is (2) 2 kg, because the mass of the object stays the same and that is what you are asked for. </span>
<span>Someone was trying to be tricky.</span>
Answer: C. 39 s
Explanation:
We know the constant speed is 0.22 m/s. We have to get to 8.5 m. We divide <u>8.5 m by 0.22</u> = 38.6. After we estimate, 6 is greater than 5, so 39 s.