Answer:
At low pressure-
At high pressure-
Explanation:
Initial speed,
Final speed,
Net horizontal force due to rolling friction
mg where m is mass, g is acceleration due to gravity,
is coefficient of rolling friction
From kinematic relation,
For each tire,
Making
the subject
Under low pressure of 40 Psi, d=18 m
Therefore,
At a pressure of 105 Psi, d=93.7
Therefore,
Answer:
Magnesium atomic no. = 24,25,26. These are the two elements which have same atomic no
Explanation:
The text does not specify whether the resistance R of the wire must be kept the same or not: here I assume R must be kept the same.
The relationship between the resistance and the resistivity of a wire is

where

is the resistivity
A is the cross-sectional area
R is the resistance
L is the wire length
the cross-sectional area is given by

where r is the radius of the wire. Substituting in the previous equation ,we find

For the new wire, the length L is kept the same (L'=L) while the radius is doubled (r'=2r), so the new resistivity is

Therefore, the new resistivity must be 4 times the original one.