Answer:
D, the acceleration of A is twice that of b.
Explanation: in four seconds b got to ten, in two seconds a got to 20. Going 10m/s faster in half the time is going twice the acceleration
Answer:
|v| = 8.7 cm/s
Explanation:
given:
mass m = 4 kg
spring constant k = 1 N/cm = 100 N/m
at time t = 0:
amplitude A = 0.02m
unknown: velocity v at position y = 0.01 m

1. Finding Ф from the initial conditions:

2. Finding time t at position y = 1 cm:

3. Find velocity v at time t from equation 2:

Answer:
The acceleration of the train is 5 m/s².
Explanation:
Acceleration is the change in velocity over a given time interval.
Therefore, acceleration is given as:

Where,
are initial and final velocities and
is the time interval.
Here, 
This gives,

Therefore, the acceleration of the train is 5 m/s².