A rollercoaster car has 2500 J of potential energy and 160 J of

The diagram shows the flow of water through a hydroelectric power station. The falling water

KonstantinChe [14]

Answer:

KE = $\frac{1}{2}$ m $v^{2}$

Explanation:

In the generation of energy from hydroelectric power station, the motion of water, and the turbines are paramount. The falling flowing water turns the blades of the turbine, which in-turn causes the movement of a coil within a strong magnetic field.

The motion of the coil which cuts the strong magnetic field induces current. Thus, the system generates electrical energy.

The equation that links kinetic energy (KE), mass (m) and speed (v) can be expressed as:

KE = $\frac{1}{2}$ m $v^{2}$

7 0

3 years ago

Susan works in the research and development department. She has recently purchased a large high-speed external drive and has att

ivann1987 [24]

The reason why Susan's drive is not working is that she has connected the drive to a USB 2.0 port, which does not have enough power for her drive.

USB is a short acronym for the original word called a Universal Serial Bus. USB is a connector interface for connecting a computer to peripherals and other devices.

USB comes in different specs such as the:

USB 2.0
USB 3.0

Some of the characteristics differences between USB 2.0 and 3.0 are:

A USB 2.0 requires 480 Mbps for data transfer speed while USB 3.0 requires 4800 Mbps.

A USB 2.0 has the ability to use a maximum power of 500 mA, while USB 3.0 can make use of up to 900 mA.

From the given information, It is stated that the drive requires a minimum of 400 Mbps and at least 900 mA;

Therefore, it implies that the drive is supposed to work with a power of at least 900 mA for it to work.

But since it is not working, we can conclude that the drive is connected to a USB 2.0 port (500 mA) which does not have enough power for the drive.

Learn more about the USB port here:

brainly.com/question/13714615

5 0

2 years ago

A. A land speed car can decelerate at 9.8m/s. How long does it take the car to come to a complete stop from a run of 885 km/hr (

Nimfa-mama [501]

Answer:

A. 25.08 s

B. 3082.53 m

C. 3×10⁵ m/s²

Explanation:

A. Determination of the time.

This can be obtained as illustrated below:

Acceleration (a) = –9.8 m/s²

Initial velocity (u) = 245.8 m/s

Final velocity (v) = 0 m/s

Time (t) =.?

v = u + at

0 = 245.8 + (–9.8 × t)

0 = 245.8 – 9.8t

Collect like terms

0 – 245.8 = – 9.8t

– 245.8 = – 9.8t

Divide both side by –9.8

t = –245.8 / –9.8

t = 25.08 s

Therefore, it will take 25.08 s for the car to come to a complete stop.

B. Determination of the distance travelled by the car.

Acceleration (a) = –9.8 m/s²

Initial velocity (u) = 245.8 m/s

Final velocity (v) = 0 m/s

Distance (s) =?

v² = u² + 2as

0² = 245.8² + (2 × –9.8 × s)

0 = 60417.64 – 19.6s

Collect like terms

0 – 60417.64 = – 19.6s

– 60417.64 = – 19.6s

Divide both side by –19.6

s = –60417.64 / –19.6

s = 3082.53 m

Thus, the car travelled a distance of 3082.53 m before stopping completely.

C. Determination of the acceleration of the object.

Initial velocity (u) = 0 m/s

Final velocity (v) = 600 m/s

Distance (s) = 0.6 m

Acceleration (a) =?

v² = u² + 2as

600² = 0² + (2 × a × 0.6)

360000 = 0 + 1.2a

360000 = 1.2a

Divide both side by 1.2

a = 360000 / 1.2

a = 300000 = 3×10⁵ m/s²

7 0

3 years ago

An uncrewed mission to the nearest star, Proxima Centauri, is launched from the Earth's surface as a projectile with an initial

Anna [14]

Answer:

42.96 km/s

Explanation:

From the conservation of Energy

$(PE+KE)_i=(PE+KE)_f\\\Rightarrow -\frac{GmM}{R}+\frac{1}{2}mv_i^2=0+\frac{1}{2}mv_f^2$

Mass gets cancelled

$-\frac{GM}{R}+\frac{1}{2}v_i^2=0+\frac{1}{2}v_f^2\\\Rightarrow -2\frac{GM}{R}+v_i^2=v_f^2\\\Rightarrow -v_e^2+v_i^2=v_f^2\\\Rightarrow v_f=\sqrt{v_i^2-v_e^2}$

$v_e=\sqrt{\frac{2Gm}{R}}$ = Escape velocity of Earth = 11.2 km/s

$v_i$ = Velocity of projectile = 44.4 km/s

$v_f=\sqrt{44.4^2-11.2^2}\\\Rightarrow v_f=42.96\ km/s$

The velocity of the spacecraft when it is more than halfway to the star is 42.96 km/s

6 0

3 years ago

1. Most waves are caused by vibrations. What motion in a transmitting antenna causes the vibrations that produce radio waves?

morpeh [17]

The answer 1 is
The best-known use of radio waves is for communication; television, cellphones and radios all receive radio waves and convert them to mechanical vibrations in the speaker to create sound waves that can be heard.Electromagnetic radiation is transmitted inwaves or particles at different wavelengths and frequencies.

the answer 2 is

Radio Waves: Instant Communication
Microwaves: Data and Heat

i think the answer number 3 is
It is all about wavelength versus tunnel diameter. The wavelength of GPS is about 20cm it would happily propagate in any normal tunnel if it could get in but the earth and other structures absorb it. AM radio (600kHz - 1500kHz) cannot propagate in any normal tunnel because the wavelength is too long (500m-200m) relative to the diameter, and thus gets reflected at the entrance. FM (100MHz ~ 3m) would propagate and it does for a while but then it suffers reflections

8 0

3 years ago

Read 2 more answers