Which one doesn't belong in the group? oxygen, sulfur, selenium,

A car leaves an intersection traveling west. Its position 4 sec later is 21 ft from the intersection. At the same time, another

Alex_Xolod [135]

Answer:

15.8 ft/s

Explanation:

$\frac{da}{dt}$ = Velocity of car A = 9 ft/s

a = Distance car A travels = 21 ft

$\frac{db}{dt}$ = Velocity of car B = 13 ft/s

b = Distance car B travels = ft

c = Distance between A and B after 4 seconds = √(a²+b²) = √(21²+28²) = √1225 ft

From Pythagoras theorem

a²+b² = c²

Now, differentiating with respect to time

$2a\frac{da}{dt}+2b\frac{db}{dt}=2c\frac{dc}{dt}\\\Rightarrow a\frac{da}{dt}+b\frac{db}{dt}=c\frac{dc}{dt}\\\Rightarrow \frac{dc}{dt}=\frac{a\frac{da}{dt}+b\frac{db}{dt}}{c}\\\Rightarrow \frac{dc}{dt}=\frac{21\times 9+28\times 13}{\sqrt{1225}}\\\Rightarrow \frac{dc}{dt}=15.8\ ft/s$

∴ Rate at which distance between the cars is increasing three hours later is 15.8 ft/s

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4 years ago

What type of nuclear decay releases energy but not a particle?

statuscvo [17]

I believe gamma decay but i may be wrong

7 0

3 years ago

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1. Alcohol use causes ___________ which may lead to mistakes in judgment involving other drugs, driving, sex, and violent behavi

ankoles [38]

Alcohol use causes to reduced inhibitions that which it may be lead to mistakes in judgment with other drugs, sex, driving, and violent. When everyone drink alcohol it is bad for everyone it is for adults only ask to permission to do that.

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4 years ago

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A ball rolls down an incline, starting from rest. if the total time it takes to reach the end of the incline is t, how much time

kirill [66]

A ball rolls down an inclined plane, starting from rest. if the total time it takes to reach the end of the inclined plane is t, how much time has elapsed when it is halfway down the incline 0.5t

An inclined plane is a straightforward device with a sloping surface that is used to lift heavy objects. When friction is taken into account, the force needed to move an object up an incline is less than the weight being raised. The needed force is closer to the real weight the higher the slope or incline.

The inclined plane is the most basic of all simple machines because nothing needs to move for it to function. In order to save effort, you have to move objects farther when using an inclined plane. A variety of techniques can be used to create an inclined plane. It can be as simple as a log leaning against a tree in the woods or a piece of wood placed on the edge of a stair.

To learn more about the inclined plane please visit
brainly.com/question/14983337
#SPJ4

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2 years ago

What is the resistance of a conductor

Ivenika [448]

Opposition for the current flow

Explanation:

Resistance is defined as the ability pf the conductor to oppose the flow of electrons through it. It is usually represented in Ohm.
Resistance is an important parameter in a circuit design and it should be properly designed.
Resistance of a conductor depends upon the material nature, length of the conductor and area of cross section.
In conductor, Resistance is low. It is due to that charges flow through the conductor freely.

7 0

3 years ago