How much time is needed to push a 5,000 N car 50 meters if you are using a machine with a power of 4,500 W?

A woman rides a carnival Ferris wheel at radius 20 m, completing 6.0 turns about its horizontal axis every minute. What are (a)

natta225 [31]

Answer:

Explanation:

Given

radius of ferris wheel is 20 m

It completes 6 turns in 1 min

i.e. 1 turn in 10 sec

Therefore its angular velocity is $\omega =\frac{2\pi }{10} rad/s$

(a)Period of motion is 10 s

Magnitude of centripetal acceleration is $\omega ^2r$

$=\left ( \frac{\pi }{5}\right )^2\times 20=7.89 m/s^2$

(b)Highest point will be 40 m

(c) lowest point 0 m i.e. at ground

7 0

3 years ago

Sally takes two bar magnets and randomly tapes one end of each bar magnet. she labels the magnets A and B. She brings the taped

Artyom0805 [142]

I already answered this quesiton. The fact is that there are only two kind of poles and since the two taped poles of the magnets labeled A and B attracts one to each other, we know that the two taped poles of the first two magnets are oppsosite.

Then, the taped pole of the third magnet has to be equal to one of the first two taped poles and opposite to the other of the first two taped poles.

That drives you to conclude (predict) that when she brings the taped end of the third magnet (magnet C) near each of the first two magntes, in one case they will attract each other and in the other case they will repele mutually.

4 0

3 years ago

A fan that is rotating at 960 rev/s is turned off. It makes 1500 revolutions before it comes to a stop. a) What was its angular

Evgesh-ka [11]

Answer:

α = 1930.2 rad/s²

Explanation:

The angular acceleration can be found by using the third equation of motion:

$2\alpha \theta=\omega_f^2-\omega_i^2$

where,

α = angular acceleration = ?

θ = angular displacement = (1500 rev)(2π rad/1 rev) = 9424.78 rad

ωf = final angular speed = 0 rad/s

ωi = initial angular speed = (960 rev/s)(2π rad/1 rev) = 6031.87 rad/s

Therefore,

$2\alpha(9424.78\ rad) = (0\ rad/s)^2-(6031.87\ rad/s)^2\\\\\alpha = -\frac{(6031.87\ rad/s)^2}{(2)(9424.78\ rad)}$

<u>negative sign shows deceleration</u>

5 0

3 years ago

Relative density has no unit .why ?

Klio2033 [76]

Answer:

Relative density is a ratio of the density of a certain material to the density of a reference material. Relative density has no unit, because the units of the material in question cancel out with the units of the reference material. For example, say a cooking oil’s density is 0.9 g/cm^3.

Explanation:

7 0

3 years ago

A 55.0-kg lead ball is dropped from the Leaning Tower of Pisa. The tower is 55.0 m high. What is the speed of the ball after it

PolarNik [594]

Answer:

The speed of the ball is 9.07 m/s.

Explanation:

Given that,

Mass of the lead ball, m = 55 kg

Height of the tower, h = 55 m

We need to find the speed of the ball it has traveled 4.20 m downward, x = 4.2 meters

The initial speed of the ball will be 0 as it was at rest initially. Let v is the speed of the ball after it has traveled 4.20 m downward. It is a case of equation of motion such that :

$v^2-u^2=2ax$

$v^2=2ax$

Here, a = g

$v^2=2\times 9.8\times 4.2$

v = 9.07 m/s

So, the speed of the ball is 9.07 m/s. Therefore, this is the required solution of given condition.

4 0

3 years ago