Answer:
<h3>
2.3125m/s²</h3>
Explanation:
Using the equation of motion v² = u²+2aS
v is the final velocity = 120km/hr
120km/hr = 120 * 1000/1 * 3600 = 33.3m/s
u is the initial velocity = 0m/s
a is the acceleration
S is the distance covered = 240m
On substituting the given parameters
33.3² = 0²+2a(240)
33.3² = 480a
1110 = 480a
a = 1110/480
a = 2.3125m/s²
Hence the minimum constant acceleration that the aircraft require to be airborne after a takeoff run of 240 m is 2.3125m/s²
Gravity increases as mass increases.
Gravity decreases when distance decreases
I hope I help.
Answer: The correct answer is option b.
Explanation: We are given that the rocket is at rest initially final velocity is 445m/s.
The acceleration of the rocket is 
To calculate the distance of rocket, we use third equation of motion, which is:

where, v = final velocity = 445m/s
u = initial velocity = 0m/s
a = acceleration = 
s = distance = ? m
Putting values in above equation, we get:

Dipper effect of an oncoming train get louder as it approaches and sound diminishes as it goes away sound traveling