20% would be probably right cuz 100% is total and 80+ what gives u 100 which is 20
Answer:
Reflection involves a change in direction of waves when they bounce off a barrier. Refraction of waves involves a change in the direction of waves as they pass from one medium to another. Refraction, or the bending of the path of the waves, is accompanied by a change in speed and wavelength of the waves.
Explanation:
HOPE THIS HELPS!!!!!!❤️
Answer: in this question, the only charge in the cavity is Q. Inside the conducting spherical shell, the electric field is zero.
While outside the shell, the electric field is given by: k(q + Q)/r²
Where;
K= is a constant which is given as, 8.99 x 10^9 N m² / C².
Q= source charge which creates the electric field
q= is the test charge which is used to measure the strength of the electric field at a given location.
r= is the radius
Explanation: Inside the conducting spherical shell, the electric field is zero since the Electric field vanishes everywhere inside the volume of a good conductor.
Answer:
299.51 m/s
Explanation:
m = mass of the bullet = 45 g = 0.045 kg
M = mass of the block = 1.55 kg
v = muzzle speed of the bullet
V = speed of bullet-block combination after the collision
μ = Coefficient of friction between the block and the surface = 0.28
d = distance traveled by the block = 13 m
V' = final speed of the bullet-block combination = 0 m/s
acceleration of the bullet-block combination due to frictional force is given as
a = - μg
using the kinematics equation
V'² = V² + 2 a d
0² = V² + 2 (- μg) d
0 = V² - 2 (μg) d
0 = V² - 2 (0.28) (9.8) (13)
V = 8.45 m/s
Using conservation of momentum for collision between bullet and block
mv = (M + m) V
(0.045) v = (1.55 + 0.045) (8.45)
v = 299.51 m/s
