1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
koban [17]
3 years ago
15

A car moving with a speed of 35 m/s sees a child standing in the

Physics
1 answer:
zlopas [31]3 years ago
6 0

Answer:

2100 N

Explanation:

v = u + at \\ 0 = 35 + a(5) \\ a =  - 7m {s}^{ - 2}  \\ \\ net \: force \:  = ma \\  = (300)(7) \\  = 2100 \: newtons

You might be interested in
To see why an MRI utilizes iron to increase the magnetic field created by a coil, calculate the current needed in a 400-loop-per
gtnhenbr [62]

Answer:

B = 4.059 x 10¹⁵ T

Explanation:

Given,

Number of loop, N = 400

radius of loop, r = 0.65 x 10⁻¹⁵ m

Current, I = 1.05 x 10⁴ A

Magnetic field at the center of the loop

B = \dfrac{\mu_0NI}{2R}

B = \dfrac{4\pi\times 10^{-7}\times 400 \times 1.05 \times 10^4}{2\times 0.65\times 10^{-15}}

B = 4.059 x 10¹⁵ T

7 0
3 years ago
Balancing carefully, three boys inch out onto a horizontal tree branch above a pond, each planning to dive in separately. The th
VikaD [51]

Answer:

what is this a riddle lol it breaks when he either jumps or lands

Explanation:

3 0
3 years ago
Look at the circuit below. What is the voltage between points C and D?
stepan [7]

Option c) 1.5 V

Explanation:

<em>As the circuit is build in series first we will find the current passing through the complete circuit. Current stays the same in each element is the series cirucuit, however, the voltage is different.</em>

Voltage is given by the following formula:

V = IR

<em>Because we have to find current through whole circuit, we will first find resistance of the whole circuit.</em>

Equivalent Resistance R(eq): R1 + R2 = 60 + 60 = 120 ohm

Current passing through whole circuit be:

I = \frac{V}{R(eq)}\\I = \frac{3}{120} = 0.025


Now we will find out the voltage between C and D:

Current stays the same in series circuit: I = 0.025 c

Resistance between C and D is, R = 60 ohm

Voltage becomes, V = IR = 0.025 * 60 = 1.5 V





7 0
3 years ago
Read 2 more answers
Consider a cyclotron in which a beam of particles of positive charge q and mass m is moving along a circular path restricted by
Ulleksa [173]

A) v=\sqrt{\frac{2qV}{m}}

B) r=\frac{mv}{qB}

C) T=\frac{2\pi m}{qB}

D) \omega=\frac{qB}{m}

E) r=\frac{\sqrt{2mK}}{qB}

Explanation:

A)

When the particle is accelerated by a potential difference V, the change (decrease) in electric potential energy of the particle is given by:

\Delta U = qV

where

q is the charge of the particle (positive)

On the other hand, the change (increase) in the kinetic energy of the particle is (assuming it starts from rest):

\Delta K=\frac{1}{2}mv^2

where

m is the mass of the particle

v is its final speed

According to the law of conservation of energy, the change (decrease) in electric potential energy is equal to the increase in kinetic energy, so:

qV=\frac{1}{2}mv^2

And solving for v, we find the speed v at which the particle enters the cyclotron:

v=\sqrt{\frac{2qV}{m}}

B)

When the particle enters the region of magnetic field in the cyclotron, the magnetic force acting on the particle (acting perpendicular to the motion of the particle) is

F=qvB

where B is the strength of the magnetic field.

This force acts as centripetal force, so we can write:

F=m\frac{v^2}{r}

where r is the radius of the orbit.

Since the two forces are equal, we can equate them:

qvB=m\frac{v^2}{r}

And solving for r, we find the radius of the orbit:

r=\frac{mv}{qB} (1)

C)

The period of revolution of a particle in circular motion is the time taken by the particle to complete one revolution.

It can be calculated as the ratio between the length of the circumference (2\pi r) and the velocity of the particle (v):

T=\frac{2\pi r}{v} (2)

From eq.(1), we can rewrite the velocity of the particle as

v=\frac{qBr}{m}

Substituting into(2), we can rewrite the period of revolution of the particle as:

T=\frac{2\pi r}{(\frac{qBr}{m})}=\frac{2\pi m}{qB}

And we see that this period is indepedent on the velocity.

D)

The angular frequency of a particle in circular motion is related to the period by the formula

\omega=\frac{2\pi}{T} (3)

where T is the period.

The period has been found in part C:

T=\frac{2\pi m}{qB}

Therefore, substituting into (3), we find an expression for the angular frequency of motion:

\omega=\frac{2\pi}{(\frac{2\pi m}{qB})}=\frac{qB}{m}

And we see that also the angular frequency does not depend on the velocity.

E)

For this part, we use again the relationship found in part B:

v=\frac{qBr}{m}

which can be rewritten as

r=\frac{mv}{qB} (4)

The kinetic energy of the particle is written as

K=\frac{1}{2}mv^2

So, from this we can find another expression for the velocity:

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

And substitutin into (4), we find:

r=\frac{\sqrt{2mK}}{qB}

So, this is the radius of the cyclotron that we must have in order to accelerate the particles at a kinetic energy of K.

Note that for a cyclotron, the acceleration of the particles is achevied in the gap between the dees, where an electric field is applied (in fact, the magnetic field does zero work on the particle, so it does not provide acceleration).

6 0
3 years ago
If your
Oxana [17]
What are you asking?
4 0
3 years ago
Read 2 more answers
Other questions:
  • What is the current through a 11v bulb with a power of 99w
    14·1 answer
  • Lenses can be found in a variety of objects which example does not have a lens?
    14·2 answers
  • The four terrestrial planets are so called because they ?
    12·2 answers
  • a stone is vertically thrown upward with the velocity of 72km/hr find the maximum height reached the height​
    6·1 answer
  • A hammer falls from the top of a tall building. Ignoring air resistance, how far down will it fall in 3 secs
    15·1 answer
  • A hot air balloon is traveling vertically upward at a constant speed of 4.5 m/s. When it is 28 m above the ground, a package is
    8·1 answer
  • The picture below was taken in the Maldives.
    14·1 answer
  • A force of 30.0 N is applied to a 3.00 kg object for 3.00 seconds. Calculate the velocity experienced by the object.
    8·1 answer
  • Tristan is an engineer working on a design for a new roller coaster. He wants the car to shoot out of the station very fast but
    15·1 answer
  • Which phrase desenbes an irregular galaxy ?
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!