A helicopter's speed increases from 30m/s to 40m/s in 5 seconds. What is the acceleration of this helicopter?

A sample of helium behaves as an ideal gas as energy is

alisha [4.7K]

Answer:

0.0321 g

Explanation:

Let helium specific heat $c_h = 5.193 J/g K$

Assuming no energy is lost in the process, by the law of energy conservation we can state that the 20J work done is from the heat transfer to heat it up from 273K to 393K, which is a difference of ΔT = 393 - 273 = 120 K. We have the following heat transfer equation:

$E_h = m_hc_h \Delta T = 20 J$

where $m_h$ is the mass of helium, which we are looking for:

$m_h = \frac{20}{c_h \Delta T} = \frac{20}{5.193 * 120} \approx 0.0321 g$

4 0

3 years ago

Special relativity can be used to study an object in which frame of reference?

Tresset [83]

Special relativity led the path for general relativity; special relativity is in a sense a special application of the rules of general relativity. While general relativity is in position to tackle all of these problems, special relativity can tackle only problems in inertial frames. Inertial frame means that the frame of reference is inot accelerating. So, we disqualify answers A and D. However, remember that moving in a circle means that there is an acceleration, the centrifugal one, even if the speed does not change. Hence C is also incorrect.
The correct answer is B, since if there is no change in velocity, the frame does not accelerate and it is inertial.

3 0

3 years ago

Read 2 more answers

Which phrase does not describe a mineral?

Jobisdone [24]

The answer is A) specific chemical consumption

3 0

3 years ago

Read 2 more answers

The spin cycle of a clothes washer extracts the water in clothing by greatly increasing the water's apparent weight so that it i

andreyandreev [35.5K]

The apparent weight of a 1.1 g drop of water is 4.24084 N.

<h3>What is Apparent Weight?</h3>

According to physics, an object's perceived weight is a characteristic that describes how heavy it is. When the force of gravity acting on an object is not counterbalanced by a force of equal but opposite normality, the apparent weight of the object will differ from the actual weight of the thing.
By definition, an object's weight is equal to the strength of the gravitational force pulling on it. It follows that even a "weightless" astronaut in low Earth orbit, with an apparent weight of zero, has almost the same weight that he would have if he were standing on the ground; this is because the gravitational pull of low Earth orbit and the ground are nearly equal.

Solution:

N = Speed of rotation = 1250 rpm

D = Diameter = 45 cm

r = Radius = 22.5 cm

M = Mass of drop = 1.1 g

Angular speed of the water = $\omega = \frac{2\pi N}{60}$

$\omega = \frac{2\pi \times 1250}{60}$

$\omega = 130.89 rad/s$

Apparent weight is given by

$W _a = M\omega^{2}R$

$W_a = 1.1 \times 10^-^3\times (130.89)^2\times 0.225$

$W_a$ = 4.24084 N

Know more about Apparent weight brainly.com/question/14323035

#SPJ4

Question:

The spin cycle of a clothes washer extracts the water in clothing by greatly increasing the water's apparent weight so that it is efficiently squeezed through the clothes and out the holes in the drum. In a top loader's spin cycle, the 45-cm-diameter drum spins at 1250 rpm around a vertical axis. What is the apparent weight of a 1.1 g drop of water?

7 0

2 years ago

A hot-air balloon is floating above a straight road. To estimate their height above the ground, the balloonists simultaneously m

Karolina [17]

Answer:

3.1 miles

Explanation:

To solve this question it is important to remember that the distance between two mile markers is approximately 1 mile

Once this is known, the question becomes very easy to solve. We make two triangle, which have the following three points

Triangle 1: Hot-Air-Balloon, Ground, Milepost 1 - With angle of depression 20

Triangle 2: Hot-Air-Balloon, Ground, Milepost 2 - With angle of depression 18

As a reminder, the angle of depression is simply the angle the balloonist's head makes with the horizontal plane to be able to see the milepost.

From this we can simply drive two formulas using the Tan function

Equation 1 - $Tan(90-18) = \frac{b+1}{h}$

Equation 2 - $Tan(90-20) = \frac{b}{h}$

Solving them simultaneously we get the value of height (h) to be 3.0852 miles or 3.1 miles

8 0

3 years ago