Answer:443.1 s
Explanation:
Given
Engine of a locomotive exerts a force of 
Mass of train
Final speed (v)
F=ma
so 

and acceleration is



Answer:
15.7 m
Explanation:
m = mass of the sled = 125 kg
v₀ = initial speed of the sled = 8.1 m/s
v = final speed of sled = 0 m/s
F = force applied by the brakes in opposite direction of motion = 261
d = stopping distance for the sled
Using work-change in kinetic energy theorem
- F d = (0.5) m (v² - v₀²)
- (261) d = (0.5) (125) (0² - 8.1²)
d = 15.7 m
Answer: Current = 2 A
Explanation:
Given that an electrical power plant generates electricity with a
current I = 50 A
Potential difference V = 20 000 V
The resistance R will be achieved by Ohms law formula which state that
V = IR
But the power generated will be the product of potential difference and the current
Power P = IV
P = 50 × 20000
P = 1, 000000 W
When the transformer steps up the potential difference to 500 000 V before it is transmitted
Power is always constant.
Using the formula for power again with
V = 500000
1000000 = 500000× I
Make I the subject of formula
Current I = 1000000/500000
Current I = 2 A
Answer:
A
B

C

D

Explanation:
Considering the first question
From the question we are told that
The spring constant is 
The potential energy is 
Generally the potential energy stored in spring is mathematically represented as 
=>
=>
=>
Considering the second question
From the question we are told that
The mass of the dart is m = 0.050 kg
Generally from the law of energy conservation

=> 
=> 
Considering the third question
The height at which the dart was fired horizontally is 
Generally from the law of energy conservation

Here KE is kinetic energy of the dart which is mathematical represented as

=> 
=> 
=> 
Considering the fourth question
Generally the total time of flight of the dart is mathematically represented as

=> 
=> 
Generally the horizontal distance from the equilibrium position to the ground is mathematically represented as

=> 
=> 