- Gas central heating is used for 5 days, using 102 kWh of energy. If 1 kWh of gas costs 7p, calculate the cost of using the central heating -

Explanation:

Given that,

Gas central heating was used for 5days

At a rate of 102kWh of energy

Then, 1 kWh = 7p

So,

The total time is 5days

t = 5days

1 day = 24hours

Then, t = 5days = 5 × 24 = 120hours

Given 102kWh, then, they consumers 102 kW in one hour, then, for the 120hours,

The total energy used is 102 × 24

Then, total energy = 2448 kWh

So, 1 kWh = 7p,

Then, 2448 kWh = 7 × 2448

2448 kWh = 17,136 p.

So, the cost of the using central heat is 17,136 p

which piece of furniture will have the most inertia and give the furniture movers the most difficulty in moving?  

answer

a 75kg dining table

force is based upon mass and acceleration.the statement is not always true.

it can be explained from newton's second law of motion.

as per newton's second law of motion the rate of change of momentum is directly proportional to the applied force and takes place along the direction of force.

mathematically it can be written as -

                                              ⇒      

here   k is the proportionality constant whose value is 1.

                                                            [a is the acceleration=dv/dt]

hence we see that force not only depends on mass and acceleration but also on velocity and rate of change of mass. force f will depend on mass and acceleration only when mass is constant.

hence the statement that force is based upon mass and acceleration is false.