I believe the answer is elements!!!!
Answer:
Q = 2.95*10^5 kJ
Explanation:
In order to calculate the energy required to melt the cooper, you first calculate the energy required to reach the boiling temperature. You use the following formula:
(1)
m: mass of cooper = 540 kg
c: specific heat of cooper = 390 J/kg°C
Tb: boiling temperature of cooper = 1080°C
T1: initial temperature of cooper = 20°C
You replace the values of the parameters in the equation (1):

Next, you calculate the energy required to melt the cooper by using the following formula:
(2)
Lf: melting constant of cooper = 134000J/kg

Finally, the total amount of energy required to melt the cooper from a temperature of 20°C is the sum of Q1 and Q2:

The total energy required is 2.95*10^5 kJ
Work = (force) x (distance) = (450 N) x (4 m) = 1,800 joules
Power = (work) / (time) = (1,800 joules) / (2 sec) = 900 watts .
Answer:
Magnetic substances: steel tank, iron ball, nickel hinge
Non magnetic substances: wooden table, glass marbles, silver medal.
Explanation:
The substances which experience a force of attraction when placed in a magnetic field are called magnetic substances. For example, iron, cobalt and nickel.
The substances which do not experiences a force of attraction when placed in a magnetic field are called non magnetic substances. For example, wood, rubber, glass, etc.
Using the average velocity formula which is total distance divided by total time. If the distance is given in km convert to m then divide by 1000 to get m and if time is given in minutes then divide by 60 to get seconds. And after converting, divide to get your final answer in m/s. Hope that helped!