Answer:
A. the internal energy stays the same
Explanation:
From the first law of thermodynamics, "energy can neither be created nor destroyed but can be transformed from one form to another.
Based on this first law of thermodynamic, the new internal energy of the gas is the same as the internal energy of the original system.
Therefore, when the partition separating the two halves of the box is removed and the system reaches equilibrium again, the internal energy stays the same.
Answer:
Distance: 4.6km Displacement= -0.2km
Explanation:
Total distance: 1.5+2.4+0.7= 4.6 km
Displacement: 1.5-2.4+0.7= -0.2km
The displacement may also be 0.2km, it just depends on if it wants it negative or not.
We use the kinematic equations,
(A)
(B)
Here, u is initial velocity, v is final velocity, a is acceleration and t is time.
Given,
,
and
.
Substituting these values in equation (B), we get
.
Therefore from equation (A),

Thus, the magnitude of the boat's final velocity is 10.84 m/s and the time taken by boat to travel the distance 280 m is 51.63 s
Answer:

Explanation:
Given:
- volume of oil in the cylinder,

- volume of the oil level when the ice is immersed,

- the volume level of oil when the ice melted,

<u>Now, therefore the volume of ice:</u>



<u>Now the volume of water:</u>



As we know that the relative density is the ratio of density of the substance to the density of water.
<u>So, the relative density of ice:</u>
.....................(1)
as we know that density is given as:

now eq. (1)

where, m = mass of the water or the ice which remains constant in any phase



Answer:
The magnitude of the magnetic force exerted on the moving charge by the current in the wire is 2.18 x
N
The direction of the magnetic force exerted on the moving charge by the current in the wire is radially inward
Explanation:
given information:
current, I = 3 A
= +6.5 x
C
r = 0.05 m
v = 280 m/s
and direction of the magnetic force exerted on the moving charge by the current in the wire, we can use the following formula:
F = qvB sin θ
where
F = magnetic force (N)
q = electric charge (C)
v = velocity (m/s)
θ = the angle between the velocity and magnetic field
to find B we use
B = μ
I/2πr
μ
= 4π x
or 1.26 x
N/
, thus
B = 4π x
x 3 / 2π(0.05)
= 1.2 x
T
Now, we can calculate the magnitude force
F = qvB sin θ
θ = 90°, because the speed and magnetic are perpendicular
F = 6.5 x
x 280 x 1.2 x
sin 90°
= 2.18 x
N
Using the hand law, the magnetic direction is radially inward