A Tesla Roadster car accelerates from rest at a rate of 7.1m/s' for a time of 3.9s.

In which case does viscosity play a dominant role? Case A: a typical bacterium (size ~ 1 mm1 mm and velocity ~ 20 mm/s20 mm/s) i

My name is Ann [436]

Answer:

Case A

Explanation:

given,

size of bacteria = 1 mm x 1 mm

velocity = 20 mm/s

size of the swimmer = 1.5 m x 1.5 m

velocity of swimmer = 3 m/s

Viscous force

$F = \eta A \dfrac{dv}{dx}$

for the bacteria

$F = \eta \times 10^{-6}\times 20\times 10^{-3}$

$F =2\times 10^{-8} \eta\ N$

for the swimmer

$F = \eta \times 1.5^2\times 3$

$F =6.75 \eta\ N$

from the above force calculation

In case B inertial force that represent mass is more than the inertial force in case of bacteria.

Viscous force is dominant in case of bacteria.

So, In Case A viscous force will be dominant.

5 0

3 years ago

Generate description of the right hand rule for finding the magnetic field around a current carrying wire an tell how it is used

vladimir1956 [14]

Answer:

Right hand thumb rule : It is a rule used to find the magnetic field direction around current carrying wire .

Explanation:

It states that : "If you grasp conductor in your right hand such that thumb points in upward direction ,then the direction in which our finger curls gives the direction of magnetic field or magnetic lines of forces" .

This rule proves that :Current can give rise to magnetism .

Around every current carrying conductor there exist a magnetic field which can be easily felt .

According to this rule : When a current flows in upward direction ,the finger curls in anticlockwise direction and when direction of current reverses ,then the direction of field also reverses .

4 0

3 years ago

lcompute the increase in length of 500 m of copper wire when it's temperature changes from 12 degrees celsius to 32 degrees Cels

marshall27 [118]

Explanation:

step by step explanation

7 0

2 years ago

Potential difference of a battery is 2.2 V when it is connected

Alchen [17]

Answer:

1.1ohms

Explanation:

According to ohms law E = IR

If potential difference of a battery is 2.2 V when it is connected across a resistance of 5 ohm and if suddenly the voltage Falls to 1.8V then the current in the 5ohms resistor I = V/R = 1.8/5

I = 0.36A (This will be the load current).

Before we can calculate the value of the internal resistance, we need to know the voltage drop across the internal resistance.

Voltage drop = 2.2V - 1.8V = 0.4V

Then we calculate the internal resistance using ohms law.

According to the law, V = Ir

V= voltage drop

I is the load current

r = internal resistance

0.4 = 0.36r

r = 0.4/0.36

r = 1.1 ohms

6 0

3 years ago

viva [34]

An LDR's resistance changes with light intensity, while a thermistor's resistancce changes with temperature.

In dark, LDR's resistance is large and in the day/light LDR's resistance is small.

At low temperature, thermistor's resistance is large, while at large temperature it resistance is small.

In an LDR Resistance increases as light intensity falls, while in a thermistor resistance falls as temperature falls.

5 0

2 years ago