Answer:
a) Acceleration = 
b) Slow down acceleration = 0.625
c) Car travels 9.8 m
Explanation:
Acceleration = Change in velocity/Time
a) Change in velocity = 3.5-0 = 3.5 m/s
Time = 0.4 seconds
Acceleration = 
b) Change in velocity = 0 - 3.5 = -3.5 m/s
Time = 5.6 seconds
Acceleration = 
Slow down acceleration = 0.625
c) We have equation of motion, 
, where u is the initial velocity, u is the final velocity, s is the displacement and a is the acceleration.
Here v = 0 m/s, u = 3.5 m/s, a = -0.625
Substituting
So, car travels 9.8 m
The answer would be c because a surface wave travels between two different materials, like air and water.
Answer: C and D
Explanation: One of the first rule for total internal reflection to occur is that the ray must move from a dense to a less dense medium, hence refractive index of medium a must be greater than that of b.
When a ray moves from a dense to a less dense medium, the refracted ray moves away from the normal thus increasing the size of the angle of refraction (total internal refraction occurs when the angle of refraction is 90° and the angle of incidence at this point is known as the critical angle), hence the angle of incidence must be greater than the critical angle.
These points verifies option C and D
Answer:
B. blocks 2 & 3.
Explanation:
Block 1 has equal & opposite forces acting on it.
Block 2 has 5N on one side, 3N on the other. It will move in the direction the 5N of force is pushing.
Block 3 has no opposing force.
