First answer = brainliestquestion 3 onwards

3. Conservation of momentum for inelastic collisions (the trolleys collide and stick together):

v = (m₁v₁+m₂v₂)/(m₁+m₂)

Given values:

m₁ = m₂ = 1kg

v₁ = 5m/s

v₂ = 0m/s

Substitute the terms in the equation with the given values and solve for v:

v = (1×5+1×0)/(1+1)

v = 2.5m/s

4. Apply the same equation for inelastic collisions (the skaters hold on together after the collision):

v = (m₁v₁+m₂v₂)/(m₁+m₂)

m₁ = 60kg (moving skater's mass)

m₂ = 30kg (stationary skater's mass)

v₁ = 6m/s (moving skater's speed)

v₂ = 0m/s (stationary skater is at rest)

Substitute the values and solve for v:

v = (60×6+30×0)/(60+30)

v = 4m/s

5.

a) Since the car and lorry are moving as one object after the collision, multiply the sum of their masses by their velocity to get their momentum:

p = v×∑m

Given values:

m₁ = 1000kg (sports car)

m₂ = 3000kg (lorry)

v = 25 m/s

Plug in the values and solve for p:

p = 25×(1000+3000)

p = 100000

b) The conservation of momentum guarantees that the total momentum of the objects before and after the collision will be equal. Therefore the total momentum before the collision is the same as the value obtained in the previous question:

p = 100000

c) Assume the lorry was at rest before the collision.

Recall the general equation for conservation of momentum:

m₁v₁ + m₂v₂ = m₁v₁' + m₂v₂'

Given values:

m₁ = 1000kg (sports car)

m₂ = 3000kg (lorry)

v₂ = 0m/s (lorry is initially at rest)

v₁' = v₂' = 25m/s (car and lorry stick together after collision, moving at the same speed)

Plug in the given values and solve for v₁ (car's speed before the collision):

1000v₁ + 3000×0 = 1000×25 + 3000×25

v₁ = 100m/s

Is a  vector quantity  that refers to "the rate at which an object changes its position." imagine a person moving rapidly - one step forward and one step back - always returning to the original starting position. while this might result in a frenzy of activity, it would result in a zero velocity. because the person always returns to the original position, the motion would never result in a change in position. since velocity is defined as the rate at which the position changes, this motion results in zero velocity. if a person in motion wishes to maximize their velocity, then that person must make every effort to maximize the amount that they are displaced from their original position. every step must go into moving that person further from where he or she started. for certain, the person should never change directions and begin to return to the starting position.

I’m good with pshycology