Answer:
Explanation:
Let h be the height .
initial velocity in first case u = 0
final velocity v = 6 m /s
acceleration due to gravity g = 9.8 m /s²
v² = u² + 2 g h
6² = 0 + 2 x 9.8 x h
h = 1.837 m .
For second case u = 3 m /s
v² = u² + 2 gh
= 3² + 2 x 1.837 x 9.8
= 9 + 36
= 45 m
v = 6.7 m /s
Answer:
The cannonball and the ball will both take the same amount of time before they hit the ground.
Explanation:
For a ball fired horizontally from a given height, there is only a vertical acceleration on it towards the ground. This acceleration is equal to the acceleration due to gravity (g = 9.81 m/s^2). A ball dropped from a height will also only experience the same vertical acceleration downwards which is also equal to g = 9.81 m/s^2.
Therefore both the cannonball and the ball will take the same amount of time to hit the ground if they are released/fired from the same height.
Answer: The given statement is false.
Explanation:
According to Newton's third law of motion, every action has an equal and opposite reaction. So, when we apply force in one direction on an object then the object also applies a force in the opposite direction.
Hence, it is true that two forces in each pair of forces act in opposite directions.
For example, when we push a wooden box of 20 kg in the forward direction then the box will also apply a force in the opposite direction.
But the statement two forces in each pair can either both act on the same body or they can act on different bodies is false.
Answer:
The charge of ions must be balance
Explanation:
Ionic compound: It is that compound which consist of positive and negative ions and ions held together by electrostatic force.Electric force is that force which act between two charges.
The compound is neutral because negative ions is equal to positive ions in the ionic compound.
The charge of ions must be balance.It is necessary condition for writing a formula for an ionic compound.
Hence,the charge of ions must be balance is that condition which must be met when writing a formula for an ionic compound.
