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.
Answer:
a).
b).
Explanation:
a).
The work of the spring is find by the formula:
So knowing the work can find the constant K'
Solve for K'
b).
The force of the spring realice a motion so using the force and knowing the accelerations can find the mass
Answer:d
Explanation:
Given
First car is moving towards east with velocity 20 m/s
then it turns towards north then velocity is
suppose car takes t sec to change its path so average acceleration is given by
So average acceleration is towards North of west.
Answer
given,
Side of copper plate, L = 55 cm
Electric field, E = 82 kN/C
a) Charge density,σ = ?
using expression of charge density
σ = E x ε₀
ε₀ is Permittivity of free space = 8.85 x 10⁻¹² C²/Nm²
now,
σ = 82 x 10³ x 8.85 x 10⁻¹²
σ = 725.7 x 10⁻⁹ C/m²
σ = 725.7 nC/m²
change density on the plates are 725.7 nC/m² and -725.7 nC/m²
b) Total change on each faces
Q = σ A
Q = 725.7 x 10⁻⁹ x 0.55²
Q = 219.52 nC
Hence, charges on the faces of the plate are 219.52 nC and -219.52 nC
