All categories

3 years ago

In 3 seconds, a wave generator produces 15 pulses that spread over a distance of 45 centimeters. Calculate its velocity.

1 answer:

6 0

We don't even need to know how many pulses were produced
in those 3 seconds.

The beginning of the first pulse took 3 seconds to travel
45 centimeters from the generator.

Its speed is (45 cm) / (3 sec) = 15 cm/sec.

You might be interested in

A car drives on a circular road of radius R. The distance driven by the car is given by = + [where a and b are constants, and t

pishuonlain [190]

Answer:

The question is incomplete, the complete question is "A car drives on a circular road of radius R. The distance driven by the car is given by d(t)= at^3+bt [where a and b are constants, and t in seconds will give d in meters]. In terms of a, b, and R, and when t = 3 seconds, find an expression for the magnitudes of (i) the tangential acceleration aTAN, and (ii) the radial acceleration aRAD3"

answers:

a. $18a m/s^{2}$

b. $a_{rad}=\frac{(27a +b)^{2}}{R}$

Explanation:

First let state the mathematical expression for the tangential acceleration and the radial acceleration.

a. tangential acceleration is express as

$a_{tan}=\frac{d|v|}{dt} \\$

since the distance is expressed as

$d=at^{3}+bt$

the derivative is the velocity, hence

$V(t)=\frac{dd(t)}{dt}\\V(t)=3at^{2}+b\\$

hence when we take the drivative of the velocity we arrive at

$a_{tan}=\frac{dv(t)}{dt}\\ a_{tan}=6at\\t=3 \\we have \\a_{tan}=18a m/s^2$

b. the expression for the radial acceleration is expressed as

$a_{rad}=\frac{v^{2}}{r}\\a_{rad}=\frac{(3at^{2} +b)^{2}}{R}\\t=3\\a_{rad}=\frac{(27a +b)^{2}}{R}$

4 0

3 years ago

What is the current in a series circuit that has two resistors (4.0 ohms and 7.5 ohms) and a power source of 9.0 volts?

Olin [163]

-- First, we have to decide how to handle the two resistors.

The effective resistance of resistors in series is the sum
of their individual resistances. That is, they act like a single
resistor, whose resistance is the sum of all of them.

So in this question, the 4.0 ohms and the 7.5 ohms act like a
single resistor of 11.5 ohms.

-- The current in the circuit is

   (the supply voltage) / (the total resistance)

   = (9.0 volts) / (11.5 ohms)

   = 0.783... Ampere (rounded)

3 0

3 years ago

Read 2 more answers

Instructions:Select the correct answer from the drop-down menu. The Longmenshan Fault is in China. This fault was created when t

lina2011 [118]

I say Reverse Fault, Hope this helps :)

3 0

3 years ago

Betty is six years old and often asks her parents many questions. Her parents respond to her questions however trivial they may

Brums [2.3K]

This behavior helps Betty in <u>intellectual </u>development.

5 0

3 years ago

Read 2 more answers

A 1400 kg car traveling at 17.0 m/s to the south collides with a 4700 kg truck that is at rest. The car and truck stick together

STatiana [176]

Answer:

Final velocity = 7.677 m/s

KE before crash = 202300 J

KE after crash = 182,702.62 J

Explanation:

We are given;

m1 = 1400 kg

m2 = 4700 kg

u1 = 17 m/s

u2 = 0 m/s

Using formula for inelastic collision, we have;

m1•u1 + m2•u2 = (m1 + m2)v

Where v is final velocity after collision.

Plugging in the relevant values;

(1400 × 17) + (4700 × 0) = (1400 + 1700)v

23800 = 3100v

v = 23800/3100

v = 7.677 m/s

Kinetic energy before crash = ½ × 1400 × 17² = 202300 J

Kinetic energy after crash = ½(1400 + 1700) × 7.677² = 182,702.62 J

8 0

3 years ago