<u>Answer:</u>
The acceleration of the plane and the time required to reach this speed is (a)= 7.5
and time(t) = 20 seconds
<u>Explanation:
</u>
Given data Initial velocity
= 0
Final velocity (
) = 150 m/second
Distance (d) = 1500 m
We have the formula, 
which gives
= 0+2a(1500)
22500 = 3000 a
acceleration (a) = 7.5 

150 = 7.5 t
t= 150/7.5 = 20
t = 20 seconds.
Answer:
2. ( b ) zero
3. ( c ) 10 s
4. Uniform then decreasing
Explanation:
2.
Since the motion is uniform, initial and final velocity will be 0, hence acceleration will be zero.
3.
Initial velocity ( u ) = 5 m/s
Final velocity ( v ) = 35 m/s
Acceleration ( a ) 3 m/s^2
To find : Time ( t )
Formula : -
t = v - u / a
= 35 - 5 / 3
= 30 / 3
t = 10 s
Answer:
a) Andrea's initial momentum, 200 kg m/s
b) Andrea's final momentum, 0
c) Impulse, = - 200 Ns
d) The force that the seat belt exerts on Andrea, - 400 N
Explanation:
Given data,
The initial velocity of the car is, u = 40 m/s
The mass of Andrea, m = 50 kg
The time period of deceleration, a = 0.5 s
The final velocity of the car, v = 0
a) Andrea's initial momentum,
p = mu
= 50 x 40
= 200 kg m/s
b) Andrea's final momentum
P = mv
= 50 x 0
= 0 kg m/s
c) Impulse
I = mv - mu
= 0 - 200
= - 200 Ns
The negative sign indicated that the momentum is decreased.
d) The force that the seat belt exerts on Andrea
F = (mv - mu)t
= (0 - 200) / 0.5
= - 400 Ns
Hence,the force that the seat belt exerts on Andrea is, - 400 N
Answer:
Acceleration due to gravity is 20
So option (E) will be correct answer
Explanation:
We have given length of the pendulum l = 2 m
Time period of the pendulum T = 2 sec
We have to find acceleration due to gravity g
We know that time period of pendulum is given by



Squaring both side


So acceleration due to gravity is 20
So option (E) will be correct answer.
I believe it's C. The wagon does not move move because the force you apply to the wagon is equal to the force it applies to you. If the maximum friction force is greater than that force the wagon will not move.