Answer:
The force that is exerted when a shopping cart is pushed is a type of push force, supplied by the muscles of the cart pusher's body.
The forces that causes a metal ball to move toward a magnet is a type of pull force that is as a result of the magnetic field forces.
Explanation:
Forces are divided into push forces that tends to accelerate a body away from the source of the force, and pull forces that accelerates the body towards the force source.
Examples of push forces includes pushing a cart, pushing a table, repulsion of two similar poles of a magnet etc. Examples of pull forces includes a attractive force between two dissimilar poles of a magnet, pulling a load by a rope, a dog pulling on a leash etc.
Answer:
Explanation:
- For diagram refer the attachment.
It is given that five cells of 2V are connected in series, so total voltage of the battery:
Three resistor of 5
, 10, 15 are connected in Series, so the net resistance:
According to ohm's law:
On substituting resultant voltage (V) as 10 V and resultant resistant, as 30 
we get:
The electric current passing through the above circuit when the key is closed will be <u>0.33 A</u>
Answer:
20 m
Explanation:
From the equation of motion,
S = ut+1/2gt²................................. Equation 1
Where S = Height, u = initial velocity, t = time, g = acceleration due to gravity.
Note: Because the rocked is being dropped from a height, acceleration due to gravity is positive (g), and initial velocity (u) is negative
Given: t = 2.0 s, g = 10 m/s², u = 0 m/s (dropped from height)
Substituting into equation 1
S = 0(2) + 1/2(10)(2)²
S = 5(4)
S = 20 m
Hence the height of the the cliff above the pool is 20 m
Answer:
1. In a coal-fired power plant, chemical energy is first converted to thermal energy. TRUE.
The chemical energy in the coal is converted to thermal energy when the coal is burnt to produce steam.
2. In a coal-fired power plant, approximately 2/5 of original energy in the coal is lost to heat. FALSE.
Approximately 3/5 of the original energy is lost not 2/5 so this statement is false.
3. The molecules in cold air move faster than in hot air. FALSE.
Molecules with more heat move faster than molecules with less. Molecules in cold air therefore, will move slower than molecules in hot air.
