How is sound produced? Name its three<br>characteristics.

A car travels a distance of 74 meters in 7 seconds. What is the average speed of the car?

Nuetrik [128]

Answer:

Explanation:

The average speed of the car can be found by using the formula

$s = \frac{d}{t } \\$

d is the distance

t is the time taken

From the question we have

$s = \frac{74}{7} \\ = 10.571428...$

We have the final answer as

Hope this helps you

4 0

2 years ago

A mass spectrometer is used to examine the isotopes of uranium. Ions in the beam emerge from the velocity selector at a speed of

Vsevolod [243]

Answer:

0.2 m

Explanation:

magnetic force = centripetal force

qvB = mv² / r

cancel v on both side and make r subject of the formula

r₁ = mv / qB where m = mass of ion, v = velocity of the ion

r₁ = ( 235 × 1.67 × 10⁻²⁶ × 2.81 × 10⁵) / ( 1.6 × 10⁻¹⁹ × 0.605 T) = 1139.24 × 10⁻² = 11.4 m

r₂ = ( 238 × 1.67 × 10⁻²⁶ × 2.81 × 10⁵) / ( 1.6 × 10⁻¹⁹ × 0.605 T) = 1153.78 × 10⁻² = 11.5 m

D, distance between the impact points formed = d₂ - d₁ where d₂ and d₁ represent the diameters of the charged ions

D = (2 × 11.5 m) - ( 2 × 11.4) = 2 ( 11.5 - 11.4) = 0.2 m

6 0

3 years ago

1 kg ball rolls off a 33 m high cliff, and lands 23 m from the base of the cliff. Express the displacement and the gravitational

enyata [817]

Answer:

d = <23, 33, 0> m , F_W = <0, -9.8, 0> , W = -323.4 J

Explanation:

We can solve this exercise using projectile launch ratios, for the x-axis the displacement is

x = vox t

Y Axis

y = $v_{oy}$ t - ½ g t²

It's displacement is

d = x i ^ + y j ^ + z k ^

Substituting

d = (23 i ^ + 33 j ^ + 0) m

Using your notation

d = <23, 33, 0> m

The force of gravity is the weight of the body

W = m g

W = 1 9.8 = 9.8 N

In vector notation, in general the upward direction is positive

W = (0 i ^ - 9.8 j ^ + 0K ^) N

W = <0, -9.8, 0>

Work is defined

W = F. dy

W = F dy cos θ

In this case the force of gravity points downwards and the displacement points upwards, so the angle between the two is 180º

Cos 180 = -1

W = -F y

W = - 9.8 (33-0)

W = -323.4 J

6 0

2 years ago

ListenA person on a ledge throws a ball vertically downward, striking the ground below the ledge with 200 joules of kinetic ener

polet [3.4K]

Answer:

A. 200 J

Explanation:

The initial kinetic energy depends on the initial speed, while the gravitational potential energy depends on the height, both balls are thrown with the same initial speed and from the same height. Therefore, due to the law of conservation of energy, the balls must have the same mechanical energy (the sum of both energies) when both impact the ground. Since the potential energy is zero at this point, its final kinetic energy must also be the same.

8 0

3 years ago

A car drives to the east in a time of 4 hours. Then, immediately (not realistic, but just assume this is the case for this probl

diamong [38]

Answer:

Average speed in east direction $speed=\frac{distance}{time}=\frac{28}{4}=7km/hr$

Explanation:

We have given average speed of the entire trip = 5 km/hr

First the car 4 hours then travels 12 km in 4 hours

So total time of the trip = 4+4 = 8 hours

So total distance traveled in the trip $d=speed\times time = 5\times 8=40km$

As the car travel 12 km in 4 hours to the west

So distance traveled in 4 hour in east = 40 -12 = 28 km

Time in east direction = 4 hour

So average speed in east direction $speed=\frac{distance}{time}=\frac{28}{4}=7km/hr$

4 0

2 years ago

How is sound produced? Name its threecharacteristics.​

How is sound produced? Name its threecharacteristics.