Which of the following is an example of a chemical change

lesya692 [45]

Answer:

Explanation:

unbalance force can be defined as the force that makes object slow up or down, in order words unbalanced force can be defined as anything that can alter the state of motion of an object.

an example of an unbalanced force is likened to a situation of someone inside a lift going for a meeting at the top floor, the force which propels the lift upward is unbalanced, because it is greater than the force acting on the lift.

5 0

3 years ago

To navigate, a porpoise emits a sound wave that has a wavelength of 3.3 cm. The speed at which the wave travels in seawater is 1

dedylja [7]

Answer:

$2.2\times 10^{-5} s$

Explanation:

We are given that

The wavelength of sound wave= $\lambda=3.3 cm=3.3\times 10^{-2}m/s$

1 cm/s= $10^{-2}m/s$

Speed of sound wave,v= $1522 m/s$

We have to find the period of the wave.

We know that

Frequency= $\nu=\frac{v}{\lambda}$

Using the formula

Frequency = $\frac{1522}{3.3\times 10^{-2}}=4.6\times 10^{4}$ Hz

Time period= $\frac{1}{4.6\times 10^4}=0.22\times 10^{-4}\times \frac{10}{10^1}=2.2\times 10^{-4-1}=2.2\times 10^{-5}s$

Using identity: $\frac{a^x}{a^y}=a^{x-y}$

Hence, the time period of the wave= $2.2\times 10^{-5} s$

4 0

3 years ago

The Venn diagram compares protons with neutrons. Which shared property belongs in the region marked "B"?

telo118 [61]

is there any choices?

4 0

3 years ago

Read 2 more answers

airplane in flight has a pressure difference between the lower and upper wing surface; this provides an upward force that balanc

Dvinal [7]

Answer:

4523.17365 Pa

Explanation:

m = Mass of plane = 77000 kg

F = Force = Weight = $mg$

g = Acceleration due to gravity = 9.81 m/s²

A = Total area of wings = 167 m²

The pressure difference would be

$\Delta P=\dfrac{F}{A}\\\Rightarrow \Delta P=\dfrac{77000\times 9.81}{167}\\\Rightarrow \Delta P=4523.17365\ Pa$

The pressure difference required to keep the plane aloft is 4523.17365 Pa

3 0

3 years ago

A camera operator is filming a nature explorer in the Rocky Mountains. The explorer needs to swim across a river to his campsite

julia-pushkina [17]

Answer:

<em>a. Angle= 28.82°</em>

<em>b. Approved. He will get cold but he should be able to make it across</em>

Explanation:

Velocity Vector

The velocity is a physical quantity that measures how fast or slow at a particular direction some object is moving. It must be expressed as a vector with both a magnitude and direction. If the object is confined to move in one direction, then we can use the speed as the scalar (magnitude only) equivalent of the velocity.

a.

The explorer wants to swim across a river to his campsite, as shown in the image below. The river has a velocity vr and the explorer can swim at ve in still water. If he swam directly to the campsite, he would end up in a point below it because the river would push him down. He must swim with a velocity such that he overcomes the stream but he advances to its objective. Let's call the angle he must swim at respect to the shoreline to achieve his goal. The explorer's velocity can be decomposed in its rectangular components vx and vy. To overcome the river's velocity:

$v_{ey}=v_r$