Ask question

Ask question

All categories

antiseptic1488 [7]

3 years ago

7

You have a ball in your hand above the ground at rest which you then drop. What energy is involved in each part of this situatio

n and how do we know that total mechanical energy has been conserved? Explain with and without air resistance present.

1 answer:

Juliette [100K]3 years ago

3 0

When you hold the ball, you have potential energy, when you drop the ball, you have kinetic.

You might be interested in

A Neglecting air resistance, a ball projected straight upward so it remains in the air for 10 seconds needs an initial speed of

ololo11 [35]

Answer:

The initial velocity is 50 m/s.

(C) is correct option.

Explanation:

Given that,

Time = 10 sec

For first half,

We need to calculate the height

Using equation of motion

$v^2=u^2+2gh$

$h =\dfrac{v^2}{2g}$ ....(I)

For second half,

We need to calculate the time

Using equation of motion

$h =ut+\dfrac{1}{2}gt_{2}^2$

$h=0+\dfrac{1}{2}gt_{2}^2$

$t_{2}=\sqrt{\dfrac{2h}{g}}$

Put the value of h from equation (I)

$t_{2}=\sqrt{\dfrac{2\times v^2}{g^2}}$

$t_{2}=\dfrac{v}{g}$

According to question,

$t_{1}+t_{2}=10$

$t_{1}=t_{2}$

Put the value of t₁ and t₂

$\dfrac{v}{g}+\dfrac{v}{g}=10$

$\dfrac{2v}{g}=10$

$v=\dfrac{10\times g}{2}$

Here, g = 10

The initial velocity is

$v=\dfrac{10\times10}{2}$

$v=50\ m/s$

Hence, The initial velocity is 50 m/s.

3 0

3 years ago

Plz do all plz i will give brainest and thanks to best answer do it right

lara31 [8.8K]

Answer:

I'm not really sure but I think it's choice a

5 0

3 years ago

Read 2 more answers

he electronics supply company where you work has two different resistors, R1 and R2, in its inventory, and you must measure the

Paraphin [41]

Answer:

R₁ = 50.77 Ω

Explanation:

Since, we know that:

Electric Power = P = VI

but from Ohm's Law:

V = IR

(or) I = V/R

Therefore,

P = V²/R

(OR) R = V²/P

where,

V = Battery Voltage

R = Resistance of combination

FOR SERIES COMBINATION:

R = Rs = (57 V)²/48 W

Rs = 67.69 Ω

but, we know that:

Rs = R₁ + R₂

R₁ + R₂ = 67.69 Ω

R₁ = 67.69 Ω - R₂ __________ eqn (1)

FOR PARALLEL COMBINATION:

R = Rp = (57 V)²/256 W

Rp = 12.69 Ω

but, we know that:

Rp = (R₁R₂)/(R₁ + R₂) = 12.69 Ω

using eqn (1) and value of R₁ + R₂, we get

Rp = 12.69 = R₂(67.69 - R₂)/67.69

859.08 = 67.69 R₂ - R₂²

R₂² - 67.69 R₂ + 859.08 = 0

Solving this quadratic equation we get the answers:

Either, R₂ = 50.76 Ω

Either, R₂ = 16.92 Ω

Since, it is stated in the question that R₁ > R₂. Therefore, we choose the second value. So,

<u>R₂ = 16.92 Ω</u>

using this value in eqn (1), we get:

R₁ = 67.69 Ω - 16.92 Ω

<u>R₁ = 50.77 Ω</u>

4 0

3 years ago

PLEASE HELP !!! I NEED TO PASS

zhannawk [14.2K]

Answer:

Sorry I don't know the answer .Hope other help you.sorryyyyyyyy

7 0

3 years ago

A transverse wave is traveling through a canal. If the distance between two successive crests is 3.17 m and four crests of the w

Thepotemich [5.8K]

Answer:

a. 0.18Hz

b. 0.56m/s

Explanation:

From the question we can deduct the following parameters

The wavelength, λ is define as the distance between two successful crest or trough and from the question we conclude that wavelength is 3.17m.

Also the period of the wave T can be computed as

T=22.6/4

T=5.65secs.

a. To compute the frequency, recall that frequency, F=1/period.

Hence,

F=1/5.65

F=0.18Hz

b. Next we compute the wave speed.

Wave speed=frequency *wavelength

Wave speed =0.18*3.17

Wave speed =0.56m/s

5 0

3 years ago