When the sun and moon pull at right angles to the earth wat kinda tide can yu expect

A wire is made from a material having a temperature coefficient of resistivity of 0.0003125 (°C^-1). In an experiment, we mainta

beks73 [17]

Answer:

The power decreases by 36%

Explanation:

Given:

At 20° C

Power, P₀ = 300 W

Potential difference, V = 150 volts

Now, power is given as

P = V²/R

where, R is the resistance

on substituting the values, we get

300 = 150²/R₀

or

R₀ = 75 Ω

Now, the variation of resistance with temperature is given as

R = R₀[1 + α(T - T₀)]

where, α is the temperature coefficient of resistivity = 0.0003125 (°C⁻¹)

now, at

T₀ = 20° C

R₀ = 75 Ω

for

T = 1820° C

we have

R = R₀[1 + α(T - T₀)]

substituting the values

we get

R = 75×[1 + 0.0003125 × (1820 - 20)]

or

R = 117.18 Ω

Now using the formula for power

We have,

P = V²/R

or

P = 150²/117.18 = 192 W

Therefore, the percentage change will be

= $\frac{P-P_0}{P_0}\times 100$

on substituting the values , we get

= $\frac{192-300}{300}\times 100$

= -36%

here, negative sign depicts the decrease in power

3 0

3 years ago

Read 2 more answers

A gas expands and does PV work on its surroundings equal to 319 J. At the same time, it absorbs 136 J of heat from the surroundi

LiRa [457]

Answer:

The change in energy of the gas during the process is $-1.83\times 10^{2}$ joules.

Explanation:

We can represent this process by the First Law of Thermodynamics, in which gas does work on its surroundings and absorbs heat from there to describe its change in energy. In other words:

$Q_{in} - W_{out} = \Delta E$

Where:

$Q_{in}$ - Heat absorbed by the gas, measured in joules.

$W_{out}$ - Work done by the gas, measured in joules.

$\Delta E$ - Change in energy, measured in joules.

If we know that $Q_{in} = 1.36\times 10^{2}\,J$ and $W_{out} = 3.19\times 10^{2}\,J$ , the change in energy of the gas is:

$\Delta E = 1.36\times 10^{2}\,J-3.19\times 10^{2}\,J$

$\Delta E = -1.83\times 10^{2}\,J$

The change in energy of the gas during the process is $-1.83\times 10^{2}$ joules.

3 0

3 years ago

A penny is dropped from the top of a building that is 300.0 m tall. Calculate the speed of the penny as it hits the ground. (met

Sauron [17]

We have the equation of motion $s = ut + \frac{1}{2} at^2$ , where s is the displacement, a is the acceleration, u is the initial velocity and t is the time taken.

Here s = 300 m, u = 0 m/s, a = 9.81 $m/s^2$

Substituting

$300 = 0*t+\frac{1}{2} *9.8*t^2\\ \\ 4.9t^2 = 300\\ \\ t =7.82 seconds$

Now we have v = u+at, where v is the final velocity

Here u = 0 m/s, a= 9.81 $m/s^2$ and t = 7.82 seconds

Substituting

v = 0+9.8*7.82 = 76.68 m/s

The speed with which the penny strikes the ground = 76.68 m/s.

3 0

3 years ago

A bug is sitting on the edge of a rotating disk. At what angular velocity will the bug slide off the disk if its radius is 0.241

Ivahew [28]

Answer:

ω = 3.61 rad/sec

Explanation:

Firstly, we should know that the bug will not slip if friction can provide sufficient opposing force.

μmg = mv^2/r = mω^2r

Thus;

μg = ω^2r

ω^2 = μg/r

ω = √(μg/r)

ω = √(0.321 * 9.8)/0.241

ω = √(13.05)

= 3.61 rad/sec

3 0

3 years ago

Two bikers are riding a circular

OverLord2011 [107]

ANSWER.no cause they have to be going a the same speed and I doubt that are gonna go at the same speed.

8 0

3 years ago