Answer:
Electromagnet.
Explanation:
Electric bulb and electric water heather are application of heating effect of electric current. The electromagnet is not the result of heating effect of electric current. The bulb gives light due to the heating effect similarly the water is heated or warmed by the heating effect of electric current.
Answer:
Option (d) is correct.
Explanation:
Work done is given by :
W = Fd, where F is force and d is displacement
Unit of work done :
The SI unit of force is Newton (N) and that of displacement is meter (m). So, the unit of work done is N-m. It is call Joule. It means that the unit of work done is Joule.
Power is given by rate at which the work is done. It is given by :
P = W/t, W is work done and t is time
Unit of power:
Unit of work is Joule (J) and that of time is second (s). It means that the unit of power is Watt and it is equal to Joule/second
Hence, the correct option is (d) "The unit for work is a joule. The unit for power is a watt, which is a joule per second".
Answer:
The reason behind fire in water when nail polish is added is the presence of acetone which is a flammable substance. Acetone, commonly known as dimethyl ketone or 2-propanone, is a flammable chemical in nail polish. Acetone is flammable as well as poisonous when it comes contact with moisture.
Explanation:
The reason behind fire in water when nail polish is added is the presence of acetone which is a flammable substance. Acetone, commonly known as dimethyl ketone or 2-propanone, is a flammable chemical in nail polish. Acetone is flammable as well as poisonous when it comes contact with moisture.
Answer:
The horizontal component of the 70 N force = 35·√3 N
The vertical component of the 70 N force = 35 N
Explanation:
The magnitude of the given force, F = 70 N
The angle of inclination of the given force to the horizontal, θ = 30°
By the resolution of forces, we can resolve the given force, F, into its horizontal component, Fₓ, and vertical components, 
, as follows;
The horizontal component of the given force = Fₓ = F × cos(θ)
Substituting the values, we have;
The horizontal component of the 70 N force, Fₓ = 70 × cos(30°) = 35·√3 N
The vertical component of the given force = = F × sin(θ)
Substituting the values, we have;
The vertical component of the 70 N force, = 70 × sin(30°) = 35 N.
