Salt and water is not a colloid, it is false
Given:
Mass of the rail road car, m = 2 kg
velocity of the three cars coupled system, v' = 1.20 m/s
velocity of first car,
= 3 m/s
Solution:
a) Momentum of a body of mass 'm' and velocity 'v' is given by:
p = mv
Now for the coupled system according to law of conservation of momentum, total momentum of a system before and after collision remain conserved:
(1)
where,
= velocity of the first car
= velocity of the 2 coupled cars after collision
Now, from eqn (1)


v' = 1.80 m/s
Therefore, the velocity of the combined car system after collision is 1.80 m/s
Answer : The correct option is, Number
Explanation :
The periodic table is a type of table in which the element are systematically arranged on the basis of the atomic number.
The periodic table have the groups and periods. In the periodic table, there are 7 horizontal rows of elements are known as period and 18 vertical columns of elements are known as group.
Hence, 1A, 3B, and 7A are examples of group number on the periodic table.
Answer:
True
Explanation:
Heavier objects (objects with more mass) are more difficult to move and stop. Heavier objects (greater mass) resist change more than lighter objects. Example: Pushing a bicycle or a Cadillac, or stopping them once moving. The more massive the object (more inertia) the harder it is to start or stop.