Answer:
- Direct current is a current in which electrons flow in one direction only
- Alternating current is a current in which the direction of the electron flow reverses periodically - so, half a cycle forward, half a cycle backward
There are several advantages of using alternating currents for the transmission of electricity across a country, over large distances. The main advantages are:
- The voltage of alternating currents can be easily increased/decreased by using transformers. For instance, a transformer is used at the beginning of the transmission line to increase the voltage (electricity is transmitted at high voltage in order to reduce dissipated power), and then another transformer is used before the electricity enters the houses, in order to decrease the voltage. Transformers only work with alternating currents.
- It is easy to interrupt the flow of an alternating current, because its value naturally becomes zero every half a cycle, so this is useful in case the current must be interrupted.
Answer:
Weight
Explanation:
The spring balance is used to measure weight of an object.
Answer:
Option c
Explanation:
Magnetic field lines form loops starting from north pole to south pole outside the magnet and from south pole to north pole inside the magnet.
Thus the field is such that it is directed outwards from the North pole and directed inwards to the South pole of the magnet.
A compass in a magnetic field will will comply with the magnet's North pole directing towards the magnetic field.
Organs are made of tissues
Tissues are made of cells though so it’s kinda a weird question lol
Answer:
The speed of the large cart after collision is 0.301 m/s.
Explanation:
Given that,
Mass of the cart, 
Initial speed of the cart, 
Mass of the larger cart, 
Initial speed of the larger cart, 
After the collision,
Final speed of the smaller cart, 
(as its recolis)
To find,
The speed of the large cart after collision.
Solution,
Let 
is the speed of the large cart after collision. It can be calculated using conservation of momentum as :
So, the speed of the large cart after collision is 0.301 m/s.
