Answer:
126000 J
Explanation:
Applying,
Q = cm(t₂-t₁).................. Equation 1
Where Q = Amount of heat, c = specifc heat capacity of water, m = mass of water, t₁ = Initial temperature, t₂ = Final temperature.
From the question,
Given: m = 2 kg, t₁ = 25°C, t₂ = 40°C
Constant: c = 4200 J/kg.°C
Substitute these value into equation 1
Q = 2×4200(40-25)
Q = 2×4200×15
Q = 126000 J
Answer:
Electric field acting on the electron is 127500 N/C.
Explanation:
It is given that,
Mass of an electron, 
Charge on electron, 
Initial speed of electron, u = 0
Final speed of electron, 
Distance covered, s = 2 cm = 0.02 m
We need to find the electric field required. Firstly, we will find the acceleration of the electron from third equation of motion as :



According to Newton's law, force acting on the electron is given by :
F = ma


Electric force is given by :
F = q E, E = electric field


E = 127500 N/C
So, the electric field is 127500 N/C. Hence, this is the required solution.
Answer:
Find answers below.
Explanation:
Given the following data;
Voltage = 220V
Current = 15 A
a. To find the power;
Power = current * voltage
Power = 15 * 220
Power = 3300 Watts
b. To find the energy;
Time = 8 hours = 60 * 60 * 8 = 28800 seconds
Energy = power * time
Energy = 3300 * 8
Energy = 26400
Energy = 26.4 Kwh
c. Cost = 13 cents
Cost = 13 * 31 * 26.4
Cost = 106392 cents
Answer:

Explanation:
Two identical sticky masses m are moving in the xy-plane, with their momenta at an angle of φ with one another. They are each moving at the same speed v when they collide at the origin of the coordinates and stick together. After the collision, the masses move at an angle −θ2 with respect to the +x axis at speed v2 .1. What was the angle φ?
from the principle of momentum
In a system of colliding bodies,we know that the total momentum before collision will equal to the total momentum after collision.
Take note that momentum is the product of mass and velocity
momentum before collision=momentum after collision
mass, m
u=initial velocity of the identical masses
v2=the common velocity after the collision
Note that the collision is inelastic , since they both moved with the same velocity
umcosφ+umcosφ=(m+m)v2cos−θ2
2mucosφ=2mv2cos−θ2
