Answer:
The man moves across the ice with a speed of 0.345m/s.
Explanation:
From the conservation of linear momentum, we have that the total linear momentum before the book throw is equal to the total linear momentum just after it. Since the initial velocity of the system is zero (so the initial momentum is zero), we have that:

Where
is the mass of the man,
is the mass of the book, and
and
are their velocities. Plugging in the given values, we can compute the speed of the man (ignoring the negative sign, because we care about the magnitude, not the direction):

In words, the resulting speed of the man is 0.345m/s.
The magnitude of the vector B is 10.9
A vector is a quantity which has magnitude as well as direction and it follows vector laws of addition.
To calculate the magnitude of the vector, we have to put the square of the components of the vector along the axes under the root.
Vector B has components,
x = 2.4
y = 9.8
z = 4.1
Applying the formula,
|B| = √x²+y²+z²
|B| = √(2.4)² + (9.8)² + (4.1)²
|B| = √5.76+96.04+16.81
|B| = √118.61
|B| = 10.9
Talking about the direction the the Vector B, it will be the line joining the origin with the points (2.4,9.8,4.1)
To know more about Vectors, visit,
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Answer:
12m
Explanation:
To obtain the answer to the question given, we must observe the characteristics of image formed by a plane mirror.
The image formed by a plane mirror have the following characteristics:
1. Laterally inverted.
2. Same distance as the object from the mirror.
3. Same height as the object.
4. Virtual.
With the above information, we can calculate the distance between the boy and his image as follow:
Initially:
Object distance (u) = 4m
Image distance (v) = 4m
The boy moved 2m away, therefore:
Object distance (u) = 2 + 4 = 6m
Image distanc(v) = 2 + 4 = 6m
The distance between the boy and his image will be the sum of his distance (u) and image distance (v) i.e (u + v)
The distance between the boy and his image = 6 + 6 = 12m
Therefore, the distance between the boy and his image is 12m.
The frictional force is given by F = μmg
<span>where μ is the coeficient of friction. </span>
<span>Work done by frictional force = Fd = μmgd </span>
<span>Kinetic energy "lost" = 1/2 mv² </span>
<span>Fd = μmgd = 1/2 mv² </span>
<span>The m's cancel μgd = v² / 2 </span>
<span>d = v² / 2μg </span>
<span>d = 8² / 2(0.41)(9.8) </span>
<span>d = 32 / (0.41)(9.8) </span>
<span>d = 7.96 </span>
<span>Player slides 8 m . </span>
<span>Note. In your other example μ = 0.46 and v = 4 m/s </span>
<span>d = v² / 2μg </span>
<span>= 4² / 2(0.46)(9.8) </span>
<span>= 8 / (0.46)(9.8) </span>
<span>= 1.77 or 1.8 m.
</span>
Hope i Helped :D
Answer: A)
Explanation: when an electron is placed in a magnetic field, it experiences a force.
This force is given below as
F=qvB*sinθ
F = force experienced by charge.
q = magnitude of electronic charge
v = speed of electron
B= strength of magnetic field
θ = angle between magnetic field and velocity.
What defines the force exerted on the charge is the angle between the field and it velocity.
If magnetic field is parallel to velocity, then it means that θ=0° which means sin 0 = 0, which means
F = qvB * 0 = 0.
The charge being at rest has nothing to do with the angle between magnetic field strength and velocity.