What is the frequency of a wave that has a wavelength of 3m that is traveling at a speed of 9m/s

Which statement best describes the electrons in this illustration ?

Nonamiya [84]

A. electrons are negatively charged outside nucleus

7 0

2 years ago

A car moving at 10.0 m/s encounters a depression in the road that has a circular cross-section with a radius of 30.0 m. What is

Dennis_Churaev [7]

Answer:

F = 789 Newton

Explanation:

Given that,

Speed of the car, v = 10 m/s

Radius of circular path, r = 30 m

Mass of the passenger, m = 60 kg

To find :

The normal force exerted by the seat of the car when the it is at the bottom of the depression.

Solution,

Normal force acting on the car at the bottom of the depression is the sum of centripetal force and its weight.

$N=mg+\dfrac{mv^2}{r}$

$N=m(g+\dfrac{v^2}{r})$

$N=60\times (9.81+\dfrac{(10)^2}{30})$

N = 788.6 Newton

N = 789 Newton

So, the normal force exerted by the seat of the car is 789 Newton.

6 0

2 years ago

A baby stroller is a rest on top of a hill which is 10 m high. The stroller and baby have a mass of 20 kg. What is the potential

Anettt [7]

The potential energy is defined as the energy is contained in the body due to the height over the surface of the earth and it is calculated from the equation

$PE=mgh$

<em>where:</em>

PE: the potential energy in Joules.
m: the mass of the body in kg.
g: the acceleration due to the gravity in m/ $s^2$
h: the height of the body over the earth in meters.

<em>in our problem:</em>

$PE=20*9.8*10=1960 J$

6 0

2 years ago

A 2 300-kg pile driver is used to drive a steel I-beam into the ground. The pile driver falls 3.00 m before coming into contact

Mashcka [7]

Answer:

433903.8 N

Explanation:

From work energy theorem, the total work done is equivalent to change in kinetic energy. Kinetic energy is depedant on speed and since pile drive finally comes to rest, then final velocity is zero. Also, its initial velocity is not given. Therefore, the sum of work due to gravity and beam equals to zero. Work due to gravity is product of mass of pile driver, acceleration due to gravity and height while work due to beam is a product of force and distance. Substituting the given values then

2300*9.81*3+(F*0.156)=0

F=-433903.84615384615384615384615384615384615 N

Approximately, the magnitude of force is 433903.8 N and it acts upwards

6 0

3 years ago

What happens to the speed of an object when dropped at free fall

dedylja [7]

If it's not falling through air, water, smoke, or anything else,
and gravity is the only force on it, then its speed increases
at a constant rate ... 9.8 meters per second for every second
it falls. (That's the number on Earth. It's different in other places.)

3 0

3 years ago