Speed is a description of how fast an object moves; velocity is how fast and in what direction it moves. In physics, velocity is speed in a given direction. When we say a car travels at 60 km/h, we are specifying its speed.
Answer:
a)1815Joules b) 185Joules
Explanation:
Hooke's law states that the extension of a material is directly proportional to the applied force provided that the elastic limit is not exceeded. Mathematically;
F = ke where;
F is the applied force
k is the elastic constant
e is the extension of the material
From the formula, k = F/e
F1/e1 = F2/e2
If a force of 60N causes an extension of 0.5m of the string from its equilibrium position, the elastic constant of the spring will be ;
k = 60/0.5
k = 120N/m
a) To get the work done in stretching the spring 5.5m from its position,
Work done by the spring = 1/2ke²
Given k = 120N/m, e = 5.5m
Work done = 1/2×120×5.5²
Work done = 60× 5.5²
Work done = 1815Joules
b) work done in compressing the spring 1.5m from its equilibrium position will be gotten using the same formula;
Work done = 1/2ke²
Work done =1/2× 120×1.5²
Works done = 60×1.5²
Work done = 135Joules
Answer:
a) 141.6m
b) 8.4m/s
Explanation:
a) to find the total displacement you use the following formula for each trajectory. Next you sum the results:

hence, the total distance is 141.6m
b) the mean velocity of the total trajectory is given by:

hence, the mean velocity is 8.4 m/s
Answer:
a=m/f is not an equation under newton's second law
Explanation:
newton's second law of motion is represented using: f=ma
where a=v-u/t
therefore it becomes,f=m(v-u)/t
from f=ma,
a will become f/m,
m will become f/a
Answer:
The effect of your walking will create a force on the airline acting downwards, due to the weight. By Newton's thirds law the airline will exert an equal and opposite reaction force directed downwards.
Explanation:
The weight of all the passengers acts downwards on the floor of the Airplane.
The Airplane exerts an equal and opposite force on the passengers, with the help of its propulsion due to which the flight keeps on flying without falling down.
Hence by changing the frame of reference we can observe the force which is responsible for the reaction.