Answer:
B
Explanation:
Heat flows from hot to cold to lower the temperature of hot areas and increase temperature of cold areas. The end result is that the 2 areas have the same temperature, thus increasing entropy.
Answer:
a. 
b.
must be the minimum magnitude of deceleration to avoid hitting the leading car before stopping
c.
is the time taken to stop after braking
Explanation:
Given:
- speed of leading car,

- speed of lagging car,

- distance between the cars,

- deceleration of the leading car after braking,

a.
Time taken by the car to stop:

where:
, final velocity after braking
time taken


b.
using the eq. of motion for the given condition:

where:
final velocity of the chasing car after braking = 0
acceleration of the chasing car after braking

must be the minimum magnitude of deceleration to avoid hitting the leading car before stopping
c.
time taken by the chasing car to stop:


is the time taken to stop after braking
Answer:

Explanation:
m = Mass of each rod
L = Length of rod = Radius of ring
= Mass of ring
Moment of inertia of a spoke

For 8 spokes

Moment of inertia of ring

Total moment of inertia

The moment of inertia of the wheel through an axis through the center and perpendicular to the plane of the ring is
.
With the blocking of activation of clotting factors, the rate of conversion of fibrinogen to fibrin will decrease to a huge extent and this will prevent the clot formation.
Option A
<h3><u>Explanation:</u></h3>
The process of stopping of flow of blood through any wound by formation of a clot is known as blood clotting. The clot in blood is formed by conversion of the fibrinogen protein into its polymer form fibrin which forms a meshwork.
The conversion of fibrinogen to fibrin requires a lot of enzymes and factors present which is required one by one, known as the Cascade theory. Total of 13 factors are required, where there are prothrombin, thromboplastin, and different other factors. Inactivation of any of the 13 factors will lead to less conversion of fibrinogen to fibrin, thereby the rate of conversion will highly decrease.
Answer:
changing the polarity or direction of the battery changes the sign of the voltage and the current
Explanation:
The sign of current and voltage are due to established conventions.
The way that a DC circuit with negative current values is by changing the polarity of the power source or by inverting the battery, this creates that the electrons move in the opposite direction
Changing the battery also changes the direction of the power difference, since the potential from positive to negative, in most cases negative is assigned a potential of zero volts
In summary, changing the polarity or direction of the battery changes the sign of the voltage and the current