As they are Alkali metals (group 1), they are extremely reactive in both air and water so must be stored in kerosine to stop them from reacting with the air or water.
Answer:
Fm is the net force down on the metal in air
Fm / 2 is the net force down on the metal in liquid
Fl is the buoyant force on the metal due to liquid
Fm - Fl = Fm / 2 equating upward and downward forces
Fm / 2 = Fl
The specific gravity of the metal is twice that of the liquid
Note: F = M g = ρ V g since ρ = M / V
Answer:
I think the right answer is option B.
In an uniformly accelerated motion, the velocity of the object follows the law:

where

is the initial velocity, a the acceleration and t the time.
In our problem, the robot starts from rest, so the initial speed is zero:

. The robot is in free fall, so the acceleraion is the gravitational acceleration

. therefore, after a time

, the velocity is
Complete Question
The complete question is shown on the first uploaded image
Answer:
The value is 
Explanation:
From the question we are told that
The initial point is 
The terminal point is 
Generally the magnitude of the vector is mathematically represented as

=> 
=> 