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3 years ago

A car starting at 25 m/s applies its brakes, and 10 seconds later it slows down to a

Physics

1 answer:

Ira Lisetskai [31]3 years ago

3 0

Answer:

-2m/s²

Explanation:

Given parameters:

Initial velocity of the car = 25m/s

Time taken = 10s

Final velocity = 5m/s

Unknown:

Acceleration of the car = ?

Solution:

Acceleration is the rate of change of velocity with time.

It is mathematically expressed as:

Acceleration = $\frac{Final velocity - Initial velocity}{time}$

Acceleration = $\frac{5 - 25}{10}$ = -2m/s²

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The dielectric strength of rutile is 6.0 × 106 V/m, which corresponds to the maximum electric field that the dielectric can sust

VLD [36.1K]

Answer:

6.48*10⁻⁷ C

Explanation:

By definition, the capacitance of a capacitor is expressed as follows:

$C =\frac{Q}{V}$

where Q is the charge on one of the plates of the capacitor, and V the potential difference between the plates.
The maximum electric field, the potential difference, and the distance between plates are related by the following expression:

$V = E_{max} * d$

Replacing by the givens, we can find V as follows:

$V = 6.0e6 V/m * 0.00108 m= 6480 V$

Now, we can find the maximum charge Qmax, as follows:

$Q_{max} = C*V = 1e-10F* 6480 V = 6.48e-7 C$

The maximum charge that the capacitor can hold is 6.48*10⁻⁷ C.

5 0

3 years ago

Read 2 more answers

In a particular television picture tube, the measured beam current is 23.3 µA . How many electrons strike the tube screen every

zysi [14]

Answer:

Explanation:

Given that

Beam current (i)=23.3µA

And the time to strike(t)=28s

Also, a fundamental charge e=1.602×10^-19C

Then, the charge quantity is given as,

q=it

Then, q=23.3×10^-6×28

q=6.524×10^-4C

Also, the number of electron N is given as

q=Ne

Therefore, N=q/e

So, N=6.524×10-4/1.602×10^-19

N=4.072×10^15

There are 4.072×10^15 electrons strike the tube screen every 28 s.

7 0

3 years ago

A chicken flaps off the roof of the henhouse with a velocity of 4.5 m/s north. The chicken lands 2.8 seconds later. If a hungry

katrin2010 [14]

I think that it might be B?
Tell me if im wrong

8 0

3 years ago

Why doesnt food have energy

Nataly_w [17]

Food has calories which feeds your bones in your body from eating away your muscles, it doesn’t have “energy” on the other hand pop and drinks do.

3 0

4 years ago

Read 2 more answers

(a) Calculate the self-inductance of a solenoid that is

adell [148]

Answer:

a) 0.142mH

b) 14mV

Explanation:

the complete answer is:

(a) Calculate the self-inductance of a solenoid that is <ghtly wound with wire of diameter 0.10 cm, has a cross-sec<onal area of 0.90 cm2 , and is 40 cm long. (b) If the current through the solenoid decreases uniformly from 10 to 0 A in 0.10 s, what is the emf induced between the ends of the solenoid

a) the self inductance of a solenoid is given by:

$L=\frac{\mu_o N^2 A}{L}$

μo: magnetic permeability of vacuum = 4\pi*10^{-7}N/A^2

A: cross sectional area = 0.9cm^2=9*10^{-5}m

L: length of the solenoid = 40cm = 0.4m

The N turns of the wire is calculated by using the diameter of the wire:

N = (40cm)/(0.10cm)=400

By replacing in the formula you obtain:

$L=\frac{(4\pi *10^{-7}N/A^2)(400)^2(9*10^{-5}m^2))}{(0.4m)}=1.42*10^{-4}H$

the self inductance is 1.42*10^{-4}H = 0.142mH

b) to find the emf you can use:

$emf=L\frac{\Delta I}{\Delta t}=(1.42*10^{-4}H)\frac{10A-0A}{0.10s}=0.014V=14mV$

the emf induced is 14mV

4 0

3 years ago