Answer:
A. 420 J
Explanation:
Given the following data;
Mass = 30.45 g
Specific heat capacity = 4.18 J/g °C.
Temperature = 3.3°C
To find the quantity of heat;
Heat capacity is given by the formula;
Where;
Q represents the heat capacity or quantity of heat.
m represents the mass of an object.
c represents the specific heat capacity of water.
t represents the temperature.
Substituting into the equation, we have;
Q = 420.03 ≈ 420 Joules
Answer:
The time taken is 
Explanation:
From the question we are told that
The mass of the ball is 
The time taken to make the first complete revolution is t= 3.60 s
The displacement of the first complete revolution is 
Generally the displacement for one complete revolution is mathematically represented as

Now given that the stone started from rest 


Now the displacement for two complete revolution is


Generally the displacement for two complete revolution is mathematically represented as

=> 
=> 
So
The time taken to complete the next oscillation is mathematically evaluated as

substituting values


Answer:
the magnitude of the torque on the permanent magnet = 7.34×10⁻³ Nm
the potential energy (in J) of the system consisting of the permanent magnet and the magnetic field provided by the coils = -1.0485 ×10⁻² J
Explanation:
The torque is given by :

where ;
m = 0.160 A.m²
B = 0.0800 T
θ = 35°
So the magnitude of the torque N = mBsinθ
N = (0.160)(0.0800)(sin 35°)
N = 0.007341
N = 7.34×10⁻³ Nm
Hence, the magnitude of the torque on the permanent magnet = 7.34×10⁻³ Nm
b) The potential energy 
U = -mBcosθ
U = (- 0.160)(0.0800)(cos 45)
U = -0.010485
U = -1.0485 ×10⁻² J
Thus, the potential energy (in J) of the system consisting of the permanent magnet and the magnetic field provided by the coils = -1.0485 ×10⁻² J