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3 years ago

1. A car with a mass of 2500 kg accelerates when the traffic light turns green. If the net force

Physics

1 answer:

soldier1979 [14.2K]3 years ago

5 0

;Net force = mass of the body × acceleration of the body due to the net force

; 5000 = 2500 a...then divide both sides by 2500

; acceleration(a) = 2 m/s^2

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I can use everything on my body to advance the ball but what?

ddd [48]

The answer would be hands! hope this helps

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3 years ago

Three identical resistors are connected in parallel. The equivalent resistance increases by 630 when one resistor is removed and

strojnjashka [21]

Answer:

each resistor is 540 Ω

Explanation:

Let's assign the letter R to the resistance of the three resistors involved in this problem. So, to start with, the three resistors are placed in parallel, which results in an equivalent resistance $R_e$ defined by the formula:

$\frac{1}{R_e}=\frac{1}{R} } +\frac{1}{R} } +\frac{1}{R} \\\frac{1}{R_e}=\frac{3}{R} \\R_e=\frac{R}{3}$

Therefore, R/3 is the equivalent resistance of the initial circuit.

In the second circuit, two of the resistors are in parallel, so they are equivalent to:

$\frac{1}{R'_e}=\frac{1}{R} +\frac{1}{R}\\\frac{1}{R'_e}=\frac{2}{R} \\R'_e=\frac{R}{2} \\$

and when this is combined with the third resistor in series, the equivalent resistance ( $R''_e$ ) of this new circuit becomes the addition of the above calculated resistance plus the resistor R (because these are connected in series):

$R''_e=R'_e+R\\R''_e=\frac{R}{2} +R\\R''_e=\frac{3R}{2}$

The problem states that the difference between the equivalent resistances in both circuits is given by:

$R''_e=R_e+630 \,\Omega$

so, we can replace our found values for the equivalent resistors (which are both in terms of R) and solve for R in this last equation:

$\frac{3R}{2} =\frac{R}{3} +630\,\Omega\\\frac{3R}{2} -\frac{R}{3} = 630\,\Omega\\\frac{7R}{6} = 630\,\Omega\\\\R=\frac{6}{7} *630\,\Omega\\R=540\,\Omega$

8 0

3 years ago

The electric field of a sinusoidal electromagnetic wave obeys the equation E=(375V/m)cos[(1.99×107rad/m)x+(5.97×1015rad/s)t].a.

andrey2020 [161]

Answer:

A) max = Eo = 375 V/m, B) B = 125 10⁻⁸ T , C) f = 9.50 101⁴ Hz, D) λ = 3.158 10⁻⁷ m, E) T = 1.05 10⁻¹⁵ s , F) invisible for humans G) v = c = 3 10⁸ m/s

Explanation:

The expression given for the electric field is

E = 375 cos (1.99 107x + 5.97 105t)

The general formula for the electric field of a transverse traveler is

E = Eo cos (kx-wt)

Where k is the wave number and w the angular velocity

A) The amplitudes as electric is

Emax = Eo = 375 V / m

B) the electric and magnetic field are related

E / B = c

B = E / c

B = 375/3 108

B = 125 10⁻⁸ T

C) angular velocity and frequency is related

.w = 2π f

f = w / 2π

f = 5.97 10¹⁵ / 2π

f = 9.50 101⁴ Hz

D) the speed of light has the formula

c = λ f

λ = c / f

λ = 3 10⁸ / 9.50 10¹⁴

λ = 3.158 10⁻⁷ m

E) The period

T = 1 / f

T = 1 / 9.5 10¹⁴

T = 1.05 10⁻¹⁵ s

F) let's reduce the wavelength nm

λ = 3.158 10⁻⁷ m (10⁹nm / 1m)

λ = 3.158 10²nm = 315.3 nm

The visible radiation range is between 400nm and 700nm. This radiation is ultraviolet and is invisible humans

G) All electromagnetic radiation has a speed at the speed of light (c)

v = c = 3 10⁸ m/s

5 0

3 years ago

Mechanical energy is the difference between the kinetic and potential energies of an object. True or False?

Fofino [41]

Answer:

False

Explanation:

Its the sum of those not the difference between them

4 0

4 years ago

Read 2 more answers

How much energy is given to each coulomb of charge passing through a 6 V battery

ELEN [110]

1 volt = 1 joule per coulomb. Current doesn't actually pass 'through' a battery. But if it did, then each coulomb would gain or lose 6 joules in traversing 6 volts, depending on its sign, and whether it climbed or fell.

4 0

3 years ago