Answer:
The negative electrode of a battery has an excess of positive charge
Explanation:
This is because in every battery, there is a negative electrode ( cathode ) and only positive charge is deposited on it.
For other statements:
Batteries donot store electric charge but they store chemical energy
Some batteries donot use metals for the flow of electrons, but some use hydrogen gas at a pressure of 1 atmosphere.
Answer:
When the object is placed at the focus the image is formed at infinity.
Explanation:
When a ray passes through focus and incident on a concave mirror then it will travel parallel to principal axis after reflection.Hence the image is formed at infinity.
Answer:
14009. 72 kgms^-1
Explanation:
Momentum is the product of an objects mass and velocity
Look up pulleys problem through Khan academy and a video should pop up with a problem similar and you should be able to walk through it .
Answer:
Explained below
Explanation:
1) The human arm: This is a type of simple machine called "Lever". In this type of machine, the elbow acts as the fulcrum, the palm serves as the load because that's where we place the load we want to carry. While the inner part of the arm which is the inner part of the elbow represents the effort because that is the joint we mover when making use of our arms.
2) Pulleys: An example of this in the human body is the knee cap where the direction of an applied force is changed. Thus means as it is in motion, it alters the direction for which the quadriceps tendon pulls on the tibia.
3) wheel and axle: An example of this in the human body is the lateral rotation of the shoulder joint medial. The humerus which is the bone between the shoulder and elbow will act as the axle while the rotator will be the will because when it is rotated a little bit, the humerus will move along with it.