An aluminum rod 17.400 cm long at 20°C is heated to 100°C. What is its new length? Aluminum has a linear expansion coefficient o
f 25 × 10-6 C-1.
1 answer:
You might be interested in
Explanation:
The given data is as follows.
= 400 K,
= 500 K,
= 25 kJ = 25000 J (as 1 kJ = 1000 J)
Now, we will calculate the change in entropy as follows.
Putting the given values into the above formula as follows.
=
= 250 J/K
Hence, we can conclude that change in entropy is 250 J/K.
Answer: It takes 2.85 seconds.
Explanation: according to the question, the kinematics equation for vertical motion is
y₀ is the initial postion and equals 0 because it is fired at ground level;
v₀ is the initial speed and eqauls 14m/s;
g is gravity and it is 9.8m/s²;
y(t) is the final position and equals 0 because it is when the pumpkin hits the ground;
Rewriting the equation, we have:
0 + 14t - = 0
14t - 4.9t² = 0
t(14 - 4.9t) = 0
For this equation to be zero,
t = 0 or
14 - 4.9t = 0
- 4.9t = - 14
t =
t = 2.86
It takes 2.86 seconds for the pumpkin to hit the ground.
Answer:
59.4 N
Explanation:
The force exerted on a current-carrying wire due to a magnetic field perpendicular to the wire is given by
where
I is the current in the wire
L is the length of the wire
B is the strength of the magnetic field
Here in this problem, we model the strike as a current-carrying wire, so we have:
I = 49,500 A is the current
L = 1 m is the length (we want to find the force per each meter of length)
is the strength of the magnetic field
Therefore, the force on each meter of the current due to the magnetic field is: