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3 years ago

15

A woman lifts her 100-newton child up one meter and carries her for a distance of 50 meters to the child's bedroom. How much wor

k does the woman do?

2 answers:

tankabanditka [31]3 years ago

5 0

100 J

Please mark me brainliest it would be greatly appreciated haha

garik1379 [7]3 years ago

5 0

Answer:

100 J

Explanation:

magic

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An electron has a mass of 9.1x10-31 kg. What is

zloy xaker [14]

Answer:

3.185×10^-29 kgm/s

Explanation:

Momentum(p)=mass×velocity

=9.1×10^-31×3.5×10

=3.185×10^-29 kgm/s

4 0

3 years ago

When beryllium-7 ions (m = 11.65 × 10-27 kg) pass through a mass spectrometer, a uniform magnetic field of 0.205 T curves their

AysviL [449]

Answer:

ratio =0.3075 T

Explanation:

The magnetic field B creates a force on a moving charge such that

$F = qvB$

Now this causes a centripetal acceleration

$F = = mv^2/r$

so

$qvB = mv^2/r$ ...........(i)

$B = mv/(rq)$ ...............(ii)

If accelerating potential V is same and then kinetic energy equals the potential energy difference

$\frac{1}{2} mv^2 = Vq$

$v = \sqrt{(2Vq/m)}$ put these value in equation (ii)

$B = m\frac{\sqrt{(2Vq/m)} }{rq}$

simplifying we get

$B =m \frac{(\sqrt{ 2Vm/q})}{r}$

for same location r will be same in both case

$B_{7} = \frac{ \sqrt{(m_{7})(2V/q) }}{r}$ ..............(iii)

$B_{10} = \frac{ \sqrt{(m_{10})(2V/q) }}{r}$ ..........(iv)

dividing (iv) and (iii) equation we get

$\frac{B_{10}}{B_{7}} = \sqrt{\frac{m_{10}}{{m_7}} }$

${B_{10}} = B_{7} \sqrt{\frac{m_{10}}{{m_7}} }$

$B_{10} = 0.2574T\sqrt{\frac{ (1.663x10^-26}{(1.165x10^-26)}$

so on solving we get

=0.3075 T

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3 years ago

What does a magnetic field look like <br>

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Answer:Magnetic fields are invisible, at least usually. But scientists from NASA's Space Sciences Laboratory have made them visible as "animated photographs," using sound-controlled CGI and 3D compositing.

Explanation:

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3 years ago

The answer is -7m, but I don’t know how that’s the answer. Can anyone explain?

atroni [7]

Explanation:

At first it is in 14m position but position doesn't matter in displacement, similar case for time taken.

So at first it travels 6m in positive direction.

So displacement= 6m

Then it travels 13 in opposite or negative direction.

So displacement = 6 -13 m = -7 m

Hope it helps ya

8 0

2 years ago

Read 2 more answers

The initial kinetic energy imparted to a 0.020 kg bullet is 1200 J. (a) Assuming it

Lilit [14]

Answer:

(a) Power= 207.97 kW

(b) Range= 5768.6 meter

Explanation:

Given,

Mass of bullet, $m=0.02 kg$

Kinetic energy imparted, $K=1200 J$

Length of rifle barrel, $d=1 m$

(a)

Let the speed of bullet when it leaves the barrel is $v$ .

Kinetic energy, $K=\frac{1}{2} mv^{2}$

$v=\sqrt{\frac{2K}{m} }$

$=\sqrt{\frac{2\times1200}{0.02} }$

$=346.4m/s$

Initial speed of bullet, $u=0$

The average speed in the barrel, $v_a_v_g=\frac{u+v}{2}$

$=\frac{0+346.4}{2} \\=173.2 m/s$

Time taken by bullet to cross the barrel, $t=\frac{d}{v}$

$=\frac{1}{173.2}\\ =0.00577 second$

Power, $P_a_v_g=\frac{W}{t}$

$=\frac{1200}{0.00577} \\=207.97kW$

(b)

In projectile motion,

Maximum height, $H_m=\frac{v^2\sin^2\theta}{2g} \\$

Range, $R=\frac{v^2\sin2\theta}{g}$

given that, $H_m=R$

then, $\frac{v^2\sin^2\theta}{2g}=\frac{v^2\sin2\theta}{g}\\\sin^2\theta=2\sin\theta\cos\theta\\\\\tan\theta=4\\\theta=\tan^-^14\\\theta=75.96^0\\R=\frac{v^2\sin2\theta}{g}\\=\frac{346.4^2\times\sin(2\times75.96)}{9.8}\\5768.6 meter$

5 0

3 years ago