The density of aluminum is 2.7 g/ml.
Answer:
0.2 T
Explanation:
Magnetic field is inversely proportional to the distance from wire since the distance is halved therefore magnetic field will be doubled.
Answer:

Explanation:
Given that,
Heat required, Q = 1200 J
Mass of the object, m = 20 kg
The increase in temperature, 
We need to find the specific heat of the object. The heat required to raise the temperature is given by :

So, the specific heat of the object is
.
Entropy is an extensive property of a thermodynamic system. It quantifies the number Ω of microscopic configurations (known as microstates) that are consistent with the macroscopic quantities that characterize the system (such as its volume, pressure and temperature).[1] Under the assumption that each microstate is equally probable, the entropy
S
S is the natural logarithm of the number of microstates, multiplied by the Boltzmann constant