All categories

3 years ago

How does the current in a resistor change if the voltage across the resistor is

Physics

1 answer:

andrey2020 [161]3 years ago

3 0

Answer:

increases by a factor of 4.

Explanation:

The power dissipated through a resistor is I2RI2R

Current=IResistance=RPower=(current)2×(resistance)=I2RIf we double the current, P=(2I)2R=4I2RCurrent=IResistance=RPower=(current)2×(resistance)=I2RIf we double the current, P=(2I)2R=4I2R

Thus, doubling the current increases the power dissipated through a resistor by a factor of four.

You might be interested in

A spring loaded toy shoots straight upward with a velocity of 4.5 m/s. Determine the maximum height it reaches. Determine the ti

Angelina_Jolie [31]

Recall that

${v_y}^2-{v_{0y}}^2=2a_y(y-y_0)$

At its maximum height $y_{\mathrm{max}}$ , the toy will have 0 vertical velocity, so that

$-\left(4.5\,\dfrac{\mathrm m}{\mathrm s}\right)^2=2\left(-9.8\,\dfrac{\mathrm m}{\mathrm s^2}\right)y_{\mathrm{max}}$

$\implies y_{\mathrm{max}}=1.0\,\mathrm m$

For the toy to reach this maximum height, it takes time $t$ such that

$\dfrac{0+v_0}2t=y_{\mathrm{max}}\implies t=0.46\,\mathrm s$

which means it takes twice this time, i.e. $t=0.92\,\mathrm s$ , for the toy to reach its original position.

The velocity of the toy when it falls 1.0 m below its starting point is

${v_y}^2-\left(4.5\,\dfrac{\mathrm m}{\mathrm s}\right)^2=2\left(-9.8\,\dfrac{\mathrm m}{\mathrm s^2}\right)(0-1.0\,\mathrm m)$

$\implies{v_y}^2=39.85\,\dfrac{\mathrm m^2}{\mathrm s^2}$

$\implies v_y=-6.4\,\dfrac{\mathrm m}{\mathrm s}$

where we took the negative square root because we expect the toy to be moving in the downward direction.

6 0

3 years ago

An object 4cm high is placed 15 cm from a convex lens of focal length 18cm. Draw a ray diagram and find the position, size, and

Nataly [62]

Answer:

what I don't no really????

3 0

3 years ago

The velocity of a projectile at launch has a

arlik [135]

Answer:

1. 0 vh g

Explanation:

As air resistance is negligible, horizontal speaking, nothing is affecting the velocity. So the horizontal velocity of the projectile stays the same, vh.

As for vertical velocity, since there's always a constant gravitational acceleration acting downward, namely g, the vertical speed will decrease until it reaches the top where it is 0, it then starting to increase in magnitude, downward, due to its gravitational acceleration g.

7 0

3 years ago

A man, facing a high wall, notices that an echo is heard 4.0 seconds after he makes a sharp sound. After walking 200m directly t

cestrela7 [59]

Answer:2.4

Explanation:basically 2.4 = 2.500 kg and then we add 3.4 seconds in all of them 4.0 + 3.4 = 2.5 ok

4 0

3 years ago

A block of metal which is 20 cm on a side has a mass of 20 kg. What is it’s density? Please answer in MkS (SI) units.

Ratling [72]

The density of an object is given by:

D = M/V

D = density, M = mass, V = volume

The volume of the cube V is given by:

V = s³

where s = side length

Make a substitution:

D = M/s³

Given values:

M = 20kg, s = 20×10⁻²m

Plug in and solve for D:

D = 20/(20×10⁻²)³

D = 2500kg/m³

6 0

4 years ago