Answer:
D
Explanation:
Remember that magnets only attract at different poles. If both poles are the same, they repel
A soccer ball takes 20 s to roll 10 m.
Speed of the soccer ball
= 10/20 m/s = 1/2 m/s
Answer:(b)
Explanation:
Given
Electric current flowing through the horizontal wire towards the observer's face.
The direction of the magnetic field is given by the right-hand thumb rule, i.e. place the thumb in the direction of current and the wrapping of fingers will give the direction of the magnetic field
the direction of the magnetic field will be counterclockwise as observed by an observer.
Answer:
The output power the weightlifter is 2916.67 W.
Explanation:
Given;
weight lifted, W = 700 N
height the weight is lifted, h = 2.5 m
time taken to lift the weight, t = 0.60 s
The output power the weightlifter is calculated as;
Power = Energy applied / time taken
Energy applied = weight lifted x height the weight is lifted
Energy applied = 700 x 2.5
Energy applied = 1750 J
Power = 1750 / 0.6
Power = 2916.67 J/s = 2916.67 W.
Therefore, the output power the weightlifter is 2916.67 W.
<h2>Answer:</h2>
All the energy sources are correctly matched with their category.
Explanation:
Renewable energy sources:
These are energy sources which can be replenished as they don't in involves the irreversible phase change.
These resources can never be ended as they can be used again and again.
Wind, geothermal, biomass, bio gas are example of renewable energy sources.
Non renewable energy sources:
These are the energy source which can never be replenished after one time use. They undergo the chemical irreversible change.
These sources are lacking with the passage of time because they can never be reused.
Oil, gas, coal and natural gas are examples.
