Answer:
The change of the volume of the device during this cooling is 
Explanation:
Given that,
Mass of oxygen = 10 g
Pressure = 20 kPa
Initial temperature = 110°C
Final temperature = 0°C
We need to calculate the change of the volume of the device during this cooling
Using formula of change volume
Put the value into the formula
Hence, The change of the volume of the device during this cooling is
Answer:
When an electric current flows, the shape of the magnetic field is very similar to the field of a bar magnet
Explanation:
Answer:
Explanation:
The net force exerted on the mass is the sum of tension force and the external force of gravity.
is the tension force.
is the force of gravity.
where 
is the rope's radius from the fixed point.
From the net force equation above:
Hence the tension force is 6.046N
Answer:
17 °C
Explanation:
From specific Heat capacity.
Q = cm(t₂-t₁)................. Equation 1
Where Q = Heat absorb by the metal block, c = specific heat capacity of the metal block, m = mass of the metal block, t₂ = final temperature, t₁ = Initial temperature.
make t₁ the subject of the equation
t₁ = t₂-(Q/cm)............... Equation 2
Given: t₂ = 22 °C, Q = 5000 J, m = 4 kg, c = 250 J/kg.°c
Substitute into equation 2
t₁ = 22-[5000/(4×250)
t₁ = 22-(5000/1000)
t₁ = 22-5
t₁ = 17 °C
