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2 years ago

What are some human causes for global warming?

1 answer:

7 0

Answer: At present, humans are putting an estimated 9.5 billion metric tons of carbon into the atmosphere each year by burning fossil fuels, and another 1.5 billion through deforestation and other land cover changes

Explanation:

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You just explored work and heat. Now test your understanding,

Lyrx [107]

Answer:

the hotter it gets, the liquid(mercury), expands more and more, and will rise up the tube to the correct line to read the tempature

5 0

2 years ago

An ice skater at rest pushes against a sled at rest,causing both the skater and sled to move away from each other with different

astraxan [27]

Answer:

Newton's third law of motion.

Explanation:

An ice skater at rest pushes against a sled at rest,causing both the skater and sled to move away from each other with different acceleration. It is based on Newton's third law of motion.

Third law says that, for every action there is an equal; and opposite reaction. Here, action is force applied by ice skater and reaction is motion of skater and sled away from each other with different acceleration.

3 0

2 years ago

An object has a mass of 785 g and a volume of 15 cm³. What is its density? (Give your answer in g/cm³ to 2 decimal places).

Anvisha [2.4K]

Answer:

denisity = 52.33 g/c $m^{3}$

Explanation:

Density:

$d = \frac{m}{v}$

We have that m = 785 and that v = 15 c $m^{3}$ .

$d = \frac{785}{15}$

d = 52.33 $m^{3}$

4 0

2 years ago

Can anyone help?6th question.free brainliest answer...

DIA [1.3K]

There's a crest and a trough in each complete wave. So the question is describing 10 complete waves.

After that, the question becomes somewhat murky. It goes on to say "its time period is 0.2 seconds".

-- The "time period" of a wave is usually defined as the time for one complete wave. If that's what the phrase means, then ...

Frequency = ( 1/0.2sec )

Frequency = 5 Hz.

= = = = = = = = = =

BUT ... Is the question awkwardly trying to tell us that the 10 waves take 0.2 seconds ? If that's what it's saying, then ...

Frequency = (10) / (0.2 sec)

Frequency = 50 Hz .

6 0

3 years ago

A stunt driver wants to make his car jump over 8 cars parked side by side below a horizontal ramp.

Genrish500 [490]

Answer:

a) Minimum speed must he drive off the horizontal ramp = 39.78 m/s

b) Minimum speed must he drive off the horizontal ramp with 7° above the horizontal = 23.93 m/s

Explanation:

a) The height of ramp = 1.5 meter

Horizontal distance he must clear = 22 meter

The car is having horizontal motion and vertical motion. In case of vertical motion the acceleration on the car is acceleration due to gravity.

We have equation of motion, $s= ut+\frac{1}{2} at^2$ , s is the displacement, u is the initial velocity, a is the acceleration and t is the time.

In case of vertical motion initial velocity = 0 m/s, acceleration = 9.8 $m/s^2$ , we need to calculate time when displacement = 1.5 meter.

$1.5=0*t+\frac{1}{2} *9.8*t^2\\ \\ t = 0.553 seconds$

So the car has to cover a distance of 22 meter in 2.119 seconds.

So minimum speed required = 22/0.553 = 39.78 m/s

Minimum speed must he drive off the horizontal ramp = 39.78 m/s

b) When the take of angle is 7⁰ the vertical speed of car is not zero = V sin 7 = 0.122 V

So the in case of vertical motion we have initial velocity = 0.122 V, S = -1.5 meter( below ramp), acceleration = -9.8 $m/s^2$

Substituting

$-1.5=0.122V*t-\frac{1}{2} *9.8*t^2\\ \\ 4.9t^2-0.122Vt-1.5=0$

In case of horizontal motion

Horizontal speed of car = V cos 7 = 0.993V

So it has to travel 22 meter in t seconds

0.993Vt = 22, Vt = 22.155 m

Substituting in the equation $4.9t^2-0.122Vt-1.5=0$

We will get $4.9t^2-0.122*22.155-1.5=0\\ \\ t = 0.926 seconds$

Speed required = 22.155/0.926 = 23.93 m/s

Minimum speed must he drive off the horizontal ramp with 7° above the horizontal = 23.93 m/s

7 0

3 years ago