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3 years ago

Use the graph above to determine the change in speed of the object between 20 and 30 seconds?

Physics

2 answers:

allsm [11]3 years ago

4 0

Answer:

6 m/s

Explanation:

To determine the change in speed of the object, we just need to determine its speed at t = 30 s and at t = 20 s, and then calculate the difference.

The speed at t = 30 is:

v = 6 m/s

While the speed at t = 20 s is:

u = 0

Therefore, the change in speed is:

$\Delta v = v-u=6-0 = 6 m/s$

lara31 [8.8K]3 years ago

4 0

Explanation:

The attached figure shows the acceleration time graph of an object. We known that the slope of the a-t graph gives the velocity of an object. The area under the a-t graph gives the velocity of object.

In x axis, time t = 30 s- 20 s = 10 s

In y axis, acceleration, $a = 6 - 0=6\ m/s^2$

Area under the graph from 20 to 30 seconds is given by :

$A=v=\dfrac{1}{2}\times 10\times 6$

v = 30 m/s

So, the change in speed of the object is 30 m/s. Hence, this is the required solution.

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Find the Y component of 35m/s at 57 degrees from the X-axis.

rosijanka [135]

Answer:

35m/s[57o].

X = 35*Cos57 =

Y = 35*sin7 =Explanation:

learn man but there u go

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3 years ago

PLEASE ANSWER FAST In which of the following situations is the greatest amount of work accomplished? 1. A boy lifts a 2-newton b

GuDViN [60]

Explanation:

Work done is given by the product of force and displacement.

Case 1,

1. A boy lifts a 2-newton box 0.8 meters.

W = 2 N × 0.8 m = 1.6 J

2. A boy lifts a 5-newton box 0.8 meters.

W = 5 N × 0.8 m = 4 J

3. A boy lifts a 8-newton box 0.2 meters.

W = 8 N × 0.2 m = 1.6 J

4. A boy lifts a 10-newton box 0.2 meters.

W = 10 N × 0.2 m = 2 J

Out of the four options, in option (2) ''A boy lifts a 5-newton box 0.8 meters'', the work done is 4 J. Hence, the greatest work done is 4 J.

3 0

3 years ago

Two trains A and B of length 400 m each are moving on two parallel tracks with

Vinvika [58]

Answer:

The initial distance between the trains is 1450 m. 

Explanation:

In the question two trains are of equal length 400 m and moves at a uniform speed of 72 km/h. train A is moving ahead of train B. If the train B has to overtake train A it should accelerate.

Train B’s acceleration is $1m/s^2$ and it accelerated for 50 seconds.

 $a=1 m/s^2$ 

t=50 s 

initial speed u=72km/h 

we have to convert this speed into m/s 

 $u=72 \times 5/18=20 m/s$ 

Distance covered in accelerating phase $S=ut+1/2 at^2$ 

 $=20 \times 50+1/2 \times 1 \times 50^2$ 

 $=1000+1250=2250 m$ 

If a train is just behind another, the distance covered by the train located behind during overtaking phase will be equal to the sum of the lengths of the trains.

Here length of train A+length of train $B=400+400=800 m$ 

Hence the initial distance between the trains = $2250-800=1450 m$ 

6 0

3 years ago

Earth has a mass of 5,970,000 how would scientists express this in a number scientific notation

Kazeer [188]

Taking into account the definition of Scientific notation, the correct representation of 5,970,000 in scientific notation is 5.97×10⁶.

<h3>Definition of scientific notation</h3>

Scientific notation is a quick way to represent a number using powers of base 10.

The numbers are written as a product:

a×10ⁿ

where:

a is a real number greater than or equal to 1 and less than 10, to which a decimal point is added after the first digit if it is a non-integer number.
n is a whole number, which is called an exponent or an order of magnitude. Represents the number of times the point decimal is shifted. It is always an integer, positive if it is shifted to the left, negative if it is shifted to the right.

In this case, to write the number 5,970,000 in scientific notation, the following steps are performed:

The decimal point is moved to the left as many spaces until it reaches the right of the first digit. This number will be the value of a in the previous expression. Then a = 5.97
The base 10 is written with the exponent equal to the number of spaces that the decimal point moves. This is a positive number because the decimal point is shifted to the left, and it will have a value of n = 6.

Finally, the correct representation of 5,970,000 in scientific notation is 5.97×10⁶.

Learn more about scientific notation:

brainly.com/question/18073768

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2 years ago

What is the approximate velocity of the object at 5 seconds ? .

Gnoma [55]

Answer:

do you have an image?

Explanation:

3 0

3 years ago