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3 years ago

A man pulls on his dog's leash to keep him from running after a bicycle. Which term best describes this example?

2 answers:

8 0

We know the answer doesn't have to do with force because we have not identified a positive or negative axis.

Depending on what the system we are evaluating is, the sign of the work can change.

If work is done on the system, it is negative, but if work is done by the system, it is positive.

If the system we are evaluating is the leash, the work is being done by the leash, and therefore, the work is positive.

If the system we are evaluating is the dog, the work is being done on the dog, and therefore, the work is negative.

olchik [2.2K]3 years ago

7 0

Answer: so it’s negative work

Explanation:

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Help me with physics.....<br>due right now

serious [3.7K]

In any case, your mass would be<em> 68 kg </em>no matter what

3 0

2 years ago

Two separate masses on two separate springs undergo simple harmonic motion indefinitely (the surface is frictionless). In CASE 1

Artemon [7]

Answer:

$\frac{F_1}{F_2} =\frac{1}{2}$

Explanation:

Assuming the we have to find ratio maximum forces on the mass in each case

we know that in a spring mass system

F= Kx

K= spring constant

x= spring displacement

Case 1:

$F_1=2k\times d$

case 2:

$F_2=2k\times 2d$

therefore, $\frac{F_1}{F_2} = \frac{2K\times d}{2K\times 2d}$

$\frac{F_1}{F_2} =\frac{1}{2}$

4 0

3 years ago

rs. Rushing fills a balloon with hydrogen gas to demonstrate its ability to burn. Which combination could she use to produce the

anyanavicka [17]

Answer:

Mg and HCl

Explanation:

Here, we want to get the combination that could be used in the production of the needed hydrogen

An important chemical property of inorganic acids is that when they react with metals, they give off hydrogen gas in conjunction with the formation of a salt

HCl is a mineral acid while Mg is a metallic substance

So the reaction between this metal and the mineral acids will give the needed hydrogen gas to be produced

4 0

2 years ago

Read 2 more answers

In which one of the following circumstances could mechanical energy not possibly be conserved, even if friction and air resistan

qwelly [4]

Answer:

A car moves up a hill at a constant velocity

Explanation:

Since the velocity is constant, the speed is also constant and so is the kinetic energy. However, total mechanical energy is sum of gravitational potential energy and kinetic energy, and the car is moving up the hill so its potential energy rises.

Thus, in the circumstances described the mechanical energy cannot be conserved.

The correct answer is A car moving up the hill with constant velocity.

5 0

3 years ago

A bullet is accelerated down the barrel of a gun by hot gases produced in the combustion of gun powder. What is the average forc

Natali5045456 [20]

Answer:

Explanation:

Step one:

given data

mass of bullet= 0.02kg

speed v=700m/s

time taken =1.5ms= 0.0015 seconds

Step two:

we know that from the first law

F=ma-----1 first law of motion

also, we know that

a=v/t----2

put a=v/t in equation 1 we have

F=mv/t

Step three:

substitute our given data to find force

F=0.02*700/0.0015

F=14/0.0015

F=9333.33N

F=9.3kN

<u>The average force exerted is 9.3kN</u>

7 0

2 years ago