Answer:
(a) 2.5 m/s
(b) 37.5 KJ
Explanation:
(a)
From the law of conservation of momentum, Initial momentum=Final momentum
and making 
the subject then
and since 
is initial velocity of car, value given as 4 m/s, 
is the initial velocity of the three cars stuck together, value given as 2 m/s and 
is the final velocity which is unknown. By substitution
(b)
Initial kinetic energy is given by
Final kinetic energy is given by
The energy lost is given by subtracting the final kinetic energy from the initial kinetic energy hence
Energy lost=350-312.5=37.5 KJ
The third one sliding friction
Explanation:
Answer: 31 m/s due east
Explanation: this question can be solved using the law of conservation of linear momentum.
This law states that in a closed or isolated system, during collision, the vector sum of momentum before collision equals the vector sum of momentum after collision.
Momentum = mass × velocity
From our question, our parameters before collision are given below as
Mass of car = mc = 1400kg
Speed of car =vc = 31 m/s (due east)
Mass of truck = mt = 2400kg
Velocity of truck = vt = 25 m/s ( due east )
After collision
Velocity of car = ?
Velocity of truck = 34 m/s ( due east )
Vector sum of momentum before collision is given as
1400 (31) + 2400 (25) = 43400 + 60000 = 103400 kgm/s
After collision the truck is seen to move faster (v = 34 m/s) which implies that the car also moves due east .
1400 (v) + 2400(25) .... A positive value is between both momenta because they are in the same direction.
After collision, we have that
1400v + 60000
Vector sum of momentum before collision = vector sum of momentum after collision
103400 = 1400v + 60000
103400 - 60000 = 1400v
43400 = 1400v
v = 43400/ 1400
v = 31 m/s due east
Answer:
The outline of the energy transfer are;
a) Kinetic energy → Clockwork spring → Potential energy
b) Potential energy in clockwork car → Clockwork spring coil unwound → Clockwork car run
c) Chemical potential energy → Batteries in the car → Electric motors → Kinetic energy
Please find attached the drawings of the energy transfer created with MS Visio
Explanation:
The energy transfer diagrams are diagrams that can be used to indicate the part of a system where energy is stored and the form and location to which the energy is transferred
a) The energy transfer diagram for the winding up a clockwork car is given as follows;
Mechanical kinetic energy is used to wind up (turn) the clockwork car such that the kinetic energy is transformed into potential energy and stored in the wound up clockwork as follows;
Kinetic energy → Clockwork spring → Potential energy
b) Letting a wound up clockwork car run results in the conversion of mechanical potential energy into kinetic (energy due tom motion) energy as follows;
Potential energy in clockwork car → Clockwork spring coil unwound → Clockwork car run
c) The energy stored in the battery of a battery powered car is chemical potential energy. When the battery powered car runs, the chemical potential energy produces an electromotive force which is converted into kinetic energy as electric current flows from the batteries
Therefore, we have;
Chemical potential energy → Batteries in the car → Electric motors → Kinetic energy
