Answer:
the velocity of car when it passes the truck is u = 16.33 m/s
Explanation:
given,
constant speed of truck = 28 m/s
acceleration of car = 1.2 m/s²
passes the truck in 545 m
speed of the car when it just pass the truck = ?
time taken by the truck to travel 545 m
time =
time =
time =19.46 s
velocity of the car when it crosses the truck
u = 16.33 m/s
the velocity of car when it passes the truck is u = 16.33 m/s
Answer:
The answers to your questions are given below
Explanation:
22. The energy of an electromagnetic wave and it's frequency are related by the following equation:
E = hf
Where:
E => is the energy
h => is the Planck's constant
f => is the frequency
From the equation i.e E = hf, we can conclude that the energy of a wave is directly proportional to it's frequency. This implies that an increase in the frequency of the wave will lead to an increase in the energy of the wave and also, a decrease in the frequency will lead to a decrease in the energy of the wave.
23. Gamma ray and radio wave are both electromagnetic waves. All electromagnetic waves has a constant speed of 3×10⁸ m/s in space.
Thus, gamma ray and radio wave have the same speed in space.
Answer:
a) S = 2.35 10³ J/m²2
,
b)and the tape recorder must be in the positive Z-axis direction.
the answer is 5
c) the direction of the positive x axis
Explanation:
a) The Poynting vector or intensity of an electromagnetic wave is
S = 1 /μ₀ E x B
if we use that the fields are in phase
B = E / c
we substitute
S = E² /μ₀ c
let's calculate
s = 941 2 / (4π 10⁻⁷ 3 10⁸)
S = 2.35 10³ J/m²2
b) the two fields are perpendicular to each other and in the direction of propagation of the radiation
In this case, the electro field is in the y direction and the wave propagates in the ax direction, so the magnetic cap must be in the y-axis direction, and the tape recorder must be in the positive Z-axis direction.
the answer is 5
C) The poynting electrode has the direction of the electric field, by which or which should be in the direction of the positive x axis
Answer:
Correct answer is option D
- Wire is on the cylinder axis and carries current i in the direction opposite to that of the current in the shell
Explanation:
- It cannot be Option E, because the magnetic field outside the wire would not be 0 due to the current carried by the conductor
-Also, the parallel wire cannot carry current in the same direction because, that would amplify the magnetic field created by the outer cylinder (since B is dir. proportional to the current) -and now, that leaves only option C and D. If, it is Option C, then that means one side of the cylinder would be more closer to the parallel wire than the other, so there would be different B fields on the two opposite sides of the cylinder. So, that means the answer is option D.
<h3>
Answer:</h3>
49 N
<h3>
Explanation:</h3>
<u>We are given;</u>
- Mass of the brick as 3 kg
- The coefficient of friction as 0.6
We are required to determine the force that must be applied by the woman so the brick does not fall.
- We need to importantly note that;
- For the brick not to fall the, the force due to gravity is equal to the friction force acting on the brick.
- That is; Friction force = Mg
But; Friction force = μ F
Therefore;
μ F = mg
0.6 F = 3 × 9.8
0.6 F = 29.4
F = 49 N
Therefore, she must use a force of 49 N
