Answer:
3600 kg
Explanation:
From the question,
Density = Mass/Volume
D = M/V.............................. Equation 1
Where D = Density of the substance, M = mass of the substance, V = Volume of the subtance.
Make M the subject of the equation
M = D×V ............................ Equation 2
Given: D = 1200 kg/m³, V = 3 m³.
Substitute these values into equation 2
M = 1200×3
M = 3600 kg.
Hence the mass of the substance is 3600 kg
Answer:
Atoms are composed of electrons (charge -1), protons (charge +1), and neutrons (no charge). So in a neutral atom the correct answer is "D".
Answer:
a)54L/min
b)0.845
Explanation:
a) A x V=
where suffix 1,2,3 refers to the three pipes.
=27L/min+16L/min+11 L/min
=54L/min
b) A x V=54L/min => 
x v
d= 2 cm
x v = 54
v= 
x 
-> 
x 
=27L/min => 
x 
= 1.3cm
x = 27
= x 
Next is to find the ratio of speed i.e 
x / x => 
= 0.845
Answer:
Commutator is a ring which reverse the direction of current in AC circuit so that the coil connected to it will continuous to move in the same direction.
Explanation:
In motors there exist a coil which is rotated due to torque of magnetic field when current flow through it. Since AC current is used to run the motor so we know that AC current changes its direction after half cycle.
So here commutator plays an important role to reverse the direction of current after every half cycle so that the current goes in same direction always into the coil.
This will produce a constant direction torque on the coil so that it will rotate in same sense always.
So commutator role is to provide same direction current to the coil by reversing its direction after every half cycle
Answer:
The sound intensity level in the car is 57.2 dB.
Explanation:
Sound intensity level in decibels, β = 10 log (I/I₀); where I = 0.525 × 10⁻⁶ W/m², I₀ = 1.0 × 10⁻¹² W/m²
β (dB) = 10 log ((0.525 × 10⁻⁶)/(1.0 × 10⁻¹²)) = 10 × 5.72 = 57.2 dB
Hope this Helps!!!
