Answer:
Positive.
Explanation:
As a consequence of the photoelectric effect, electrons that will get hit by sufficiently energetic photons will abandon the metal surfaces exposed to bright sunlight. This decreases the negative charge of the surface, thus causing it to develop a positive net charge.
Answer:
the index of refraction of the other material = 1.31
Explanation:
Critical angle is given by the formula;
sin(θ_crit) = n_r/n_i
Where;
θ_crit is critical angle
n_r is index of refraction of the Refractive medium
n_i is index of refraction of incidence medium
We are given that θ_crit = 81° and n_i = 1.33
Thus;
sin 81 = n_r/1.33
n_r = 1.33 × sin 81
n_r = 1.33 × 0.9877
n_r ≈ 1.31
Answer:
W = 181.26 J
Explanation:
Given that,
The force acting on the cart, F = 20 N
It is at an angle of 25 degrees above the horizontal to move a crate a distance of 10m across the floor.
We need to find work done by the student. The work done by the student is given by :
So, the required work done is 181.26 J.