If both bars are made of a good conductor, then their specific heat capacities must be different. If both are metals, specific heat capacities of different metals can vary by quite a bit, eg, both are in kJ/kgK, Potassium is 0.13, and Lithium is very high at 3.57 - both of these are quite good conductors.
If one of the bars is a good conductor and the other is a good insulator, then, after the surface application of heat, the temperatures at the surfaces are almost bound to be different. This is because the heat will be rapidly conducted into the body of the conducting bar, soon achieving a constant temperature throughout the bar. Whereas, with the insulator, the heat will tend to stay where it's put, heating the bar considerably over that area. As the heat slowly conducts into the bar, it will also start to cool from its surface, because it's so hot, and even if it has the same heat capacity as the other bar, which might be possible, it will eventually reach a lower, steady temperature throughout.
Answer:
17.6 N
Explanation:
The force exerted by the punter on the football is equal to the rate of change of momentum of the football:
where
is the change in momentum of the football
is the time elapsed
The change in momentum can be written as
where
m = 0.55 kg is the mass of the football
u = 0 is the initial velocity (the ball starts from rest)
v = 8.0 m/s is the final velocity
Combining the two equations and substituting the values, we find the force exerted on the ball:
Hey there!
So we know that m*v=P.
And in this question m=30
v=5 m/s
P = 30*5 Kgm/s
P = 150 Kgm/s
So, your final answer is 150 Kg.m/s
Hope this helps! :)
Answer:
You are asked to design a cylindrical steel rod 50.0 cm long, with a circular cross section, that will conduct 170.0 J/s from a furnace at 350.0 ∘C to a container of boiling water under 1 atmosphere.
Explanation:
Given Values:
L = 50 cm = 0.5 m
H = 170 j/s
To find the diameter of the rod, we have to find the area of the rod using the following formula.
Here Tc = 100.0° C
k = 50.2
H = k × A × ![\frac{[T_{H -}T_{C} ] }{L}](https://tex.z-dn.net/?f=%5Cfrac%7B%5BT_%7BH%20-%7DT_%7BC%7D%20%5D%20%7D%7BL%7D)
Solving for A
A = ![\frac{H * L }{k * [ T_{H}- T_{C} ] }](https://tex.z-dn.net/?f=%5Cfrac%7BH%20%2A%20L%20%7D%7Bk%20%2A%20%5B%20T_%7BH%7D-%20T_%7BC%7D%20%5D%20%7D)
A = ![\frac{170 * 0.5}{50.2 * [ 350 - 100 ]}](https://tex.z-dn.net/?f=%5Cfrac%7B170%20%2A%200.5%7D%7B50.2%20%2A%20%5B%20350%20-%20100%20%5D%7D)
A = 
= 6.77 ×
m²
Now Area of cylinder is :
A = 
d²
solving for d:
d = 
d = 9.28 cm
Initial speed = 56mph
Final speed = 35mph
Time taken = 6.7seconds...
Converting the time to hour.. Divide by 3600..
= 6.7/3600
=0.00186hour..
Acceleration = v-u/t
a = 35-56/0.00186
a = -11283.6mph²
The negative sign shows that it decelerated...
V² = u²+2as
(35)² = (56)² + 2×-11283.6×s
Where s is the distance covered within that time...
1225 = 3136 - 22567.2s
22567.2s = 3136-1225
22567.2s = 1911
S = 1911/22567.2
S = 0.08468miles...
But at the end of the question we were made to understand that 1miles = 5280ft
Therefore 0.08468miles = (0.08468×5280)ft
= 447. 11feets...
Which is approximately 447ft.....
Hope this helped.... ?
