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4 years ago

13

a 40 kg boy jumps off the side of the pool. when he hits the water, he is traveling 3 m/s. how much kinetic energy does he have

right before he hits the water

1 answer:

Vladimir79 [104]4 years ago

4 0

3 m/s because when he hits the water he will be traveling at the same speed

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A 1.10 μF capacitor is connected in series with a 1.92 μF capacitor. The 1.10 μF capacitor carries a charge of +10.1 μC on one p

miss Akunina [59]

Answer:

(a). The potential on the negative plate is 42.32 V.

(b). The equivalent capacitance of the two capacitors is 0.69 μF.

Explanation:

Given that,

Charge = 10.1 μC

Capacitor C₁ = 1.10 μF

Capacitor C₂ = 1.92 μF

Capacitor C₃ = 1.10 μF

Potential V₁ = 51.5 V

Let V₁ and V₂ be the potentials on the two plates of the capacitor.

(a). We need to calculate the potential on the negative plate of the 1.10 μF capacitor

Using formula of potential difference

$V_{1}=\dfrac{Q}{C_{1}}$

Put the value into the formula

$V_{1}=\dfrac{10.1 \times10^{-6}}{1.10\times10^{-6}}$

$V_{1}=9.18\ V$

The potential on the second plate

$V_{2}=V-V_{1}$

$V_{2}=51.5 -9.18$

$V_{2}=42.32\ v$

(b). We need to calculate the equivalent capacitance of the two capacitors

Using formula of equivalent capacitance

$C=\dfrac{C_{1}\timesC_{2}}{C_{1}+C_{2}}$

Put the value into the formula

$C=\dfrac{1.10\times10^{-6}\times1.92\times10^{-6}}{(1.10+1.92)\times10^{-6}}$

$C=6.99\times10^{-7}\ F$

$C=0.69\ \mu F$

Hence, (a). The potential on the negative plate is 42.32 V.

(b). The equivalent capacitance of the two capacitors is 0.69 μF.

7 0

3 years ago

A ball is kicked from the top of a building with a velocity of 50 m/s and lands 165 m away from the base of the building.

Nadusha1986 [10]

The height of the building is 53.4 m (projectile motion)

Explanation:

The motion of the ball is a projectile motion, so it follows a parabolic path which consists of two independent motions:

- A uniform motion (constant velocity) along the horizontal direction

- An accelerated motion with constant acceleration (acceleration of gravity) in the vertical direction

First of all, we consider the horizontal motion, which is a uniform motion at constant speed. The equation that gives the horizontal distance travelled is:

$d=v_x t$

where:

$v_x = 50 m/s$ is the horizontal velocity of the ball, which is constant since there are no forces in this direction

d = 165 m is the horizontal distance travelled by the ball

Solving for t, we find the time of flight:

$t=\frac{d}{v_x}=\frac{165}{50}=3.3 s$

Now we analyze the vertical motion: it is an accelerated motion, we can use the suvat equation

$s=ut+\frac{1}{2}at^2$

where

s is the vertical displacement, which is the height of the building

u = 0 is the initial vertical velocity of the ball

t = 3.3 s is the time of flight

$a=g=9.8 m/s^2$ is the acceleration of gravity

Solving for s, we find the height of the building:

$s=0+\frac{1}{2}(9.8)(3.3)^2=53.4 m$

Learn more about projectile motion here:

brainly.com/question/8751410

#LearnwithBrainly

6 0

4 years ago

Which object moves in simple harmonic motion?\

Rina8888 [55]

<h2>Answer:Stretched rubber band with an mass</h2>

Explanation:

Simple harmonic motion requires a restoring force.

Simple harmonic motion should be periodic.

Option A:

When a rubber band is stretched,the internal forces of the rubber band pulls the band inside.So,internal forces are the restoring forces in a rubber band.

The motion is periodic as well since the the rubber band makes to an fro motion expanding ans contracting.

So,this performs SHM.

Option B:

There is no restoring force and no periodicity.

So,this is not SHM.

Option C:

There is no restoring force and no periodicity.

So,this is not SHM.

Option D:

There is periodicity but no restoring force.

So,this is not SHM.

3 0

4 years ago

Mechanical waves use matter to transfer energy. Please select the best answer from the choices provided T F

Semenov [28]

I believe the correct answer is true. Mechanical waves use matter to transfer energy. It <span> is a </span>wave<span> that is an oscillation of matter, and therefore transfers energy through a medium. Hope this answers the question. Have a nice day.</span>

8 0

4 years ago

A metal sphere has a charge of +10C. What is the net charge after 8.0 x 10^13 electrons have been placed on it?

masya89 [10]

Answer: 9.9999872 C

Explanation: In to answer this question we have to use the charge of the electron, that is eqaul to -1.6*10^-19 C.

After that, we have to calculate the charge given by 8.0*10^13 electrons, then we an additional charge of: 8.0*10^13 * -1,6*10^-19 C=1.28*10^-5C

Finally the net charge of the metal sphere, initially charged by +10C is:

10C-1.28*10^-5C=9.9999872 C

3 0

4 years ago