Their relative speed is the sum of 60 and 40 or 100km/hr. They will travel the 150km in 1.5 hrs. When two object approach each other, the closing speed is just the sum of the speeds, therefore, the closing speed is your case is 100kph. So they will meet in 1.5 hours.

8 0

3 years ago

A lamp in a child's Halloween costume flashes based on an RC discharge of a capacitor through its resistance. The effective dura

pshichka [43]

Answer:

A. 0.199 J

B. 0.0663 C

C = 0.0221 F

D. 12.68 ohms

Explanation:

From the question:

time duration, t = 0.28 seconds

Average power, P = 0.71 W

Average voltage, V = 3 V

A) Energy is given as:

E = P * t

=> E = 0.71 * 0.28 = 0.199 J

B) Electrical energy is also given as:

E = qV

where q = charge

=> q = E / V

∴ q = 0.199 / 3 = 0.0663 C

C) Capacitance is given as charge over voltage:

C = q / V

=> C = 0.0663 / 3 = 0.0221 F

D) Electrical power, P, can also be given as:

P = $V^2 / R$

where R = resistance

=> R = $V^2 / P$

R = $3^2 / 0.71 = 9 / 0.71 = 12.68 ohms$

8 0

2 years ago

un astronauta cuya masa es 80kg permanece inmovil en el espacio exterior, al activar la unidad propulsora que lleva en la espald

beks73 [17]

Answer:

Explanation:

80(0) = 2(15) + (80-2)v

v = - 0.38 m/s

5 0

2 years ago

You set out to design a car that uses the energy stored in a flywheel consisting of a uniform 80-kg cylinder of radius r that ha

Oliga [24]

E = 300km * 2000J/km = 600000J

The rotational energy is given by:
E = 0.5 * I * ω²

I for a uniform cylinder is given by:
I = 0.5 * m * r²

Resulting equation:
E = 0.25 * m * r² * ω²

Given values:
ω = 430 rev/s = 430 * 2π / s
E = 600000

Solve for r.

8 0

3 years ago