true false when testing a technological design, you may sometimes need to use a model instead of the real thing

7. A force of 100 N acting on a body gives it a speed of 200 m/s in 2

alekssr [168]

Answer:

Choice a. 1 kg, assuming that all other forces on the object (if any) are balanced.

Explanation:

By Newton's Second Law,

$\displaystyle a = \frac{\Sigma F}{m}$ ,

where

$a$ is the acceleration of the object in $\text{m}\cdot\text{s}^{-2}$ ,
$\Sigma F$ is the net force on the object in Newtons, and
$m$ is the mass of the object in kilograms.

As a result,

$\displaystyle m = \frac{\Sigma F}{a}$ .

Assume that all other forces on this object are balanced. The net force on the object will be $100\;\text{N}$ . The net force is constant. Acceleration should also be constant and the same as the average acceleration in the two seconds.

<h3>What is the average acceleration of this object?</h3>

$\displaystyle \begin{aligned}\text{Acceleration} &= \text{Average Acceleration}=\frac{\text{Change in Velocity}}{\text{Time Taken}}\end{aligned}$ .

$\displaystyle {a} = \frac{200\;\text{m}\cdot\text{s}^{-1}}{2\;\text{s}}=100\;\text{m}\cdot\text{s}^{-2}$ .

<h3>Apply Newton's Second Law to find the mass of the object.</h3>

$\displaystyle m = \frac{\Sigma F}{a} = \frac{100\;\text{N}}{100\;\text{m}\cdot\text{s}^{-2}} = 1\;\text{kg}$ .

6 0

4 years ago

Read 2 more answers

Which of the following forms matter?<br> A. Proteins<br> B.atoms<br> C.cells<br> D. DNA

Artemon [7]

Answer:b) atoms

Explanation:which are in turn made up of protons, neutrons and electrons

8 0

3 years ago

Read 2 more answers

A boy can swim 3.0 meter a second in still water while trying to swim directly across a river from west to east, he is pulled by

lana66690 [7]

Answer:

Angle: $48.19^o$

Explanation:

<u>Two-Dimension Motion</u>

When the object is moving in one plane, the velocity, acceleration, and displacement are vectors. Apart from the magnitudes, we also need to find the direction, often expressed as an angle respect to some reference.

Our boy can swim at 3 m/s from west to east in still water and the river he's attempting to cross interacts with him at 2 m/s southwards. The boy will move east and south and will reach the other shore at a certain distance to the south from where he started. It happens because there is a vertical component of his velocity that is not compensated.

To compensate for the vertical component of the boy's speed, he only has to swim at a certain angle east of the north (respect to the shoreline). The goal is to make the boy's y component of his velocity equal to the velocity of the river. The vertical component of the boy's velocity is

$v_b\ cos\alpha$

where $v_b$ is the speed of the boy in still water and $\alpha$ is the angle respect to the shoreline. If the river flows at speed $v_s$ , we now set

$v_b\ cos\alpha=v_s$

$\displaystyle cos\alpha=\frac{v_s}{v_b}=\frac{2}{3}$

$\alpha=48.19^o$

8 0

3 years ago

a sound pulse emitted underwater reflects off a school of fish and is detected at the same place 0.01 s later. how far away are

andrew-mc [135]

In fresh water sound waves travel at 1497m/s at 25 degrees, I'll assume that's the characteristics of the water.

If it's 0.01s then you need to divide the speed by 100 to get the, 14.97, however it gets there and back in that time so you need to halve it.
<u>7.485m</u>

5 0

3 years ago

Driving along a boring stretch of interstate in Illinois, you start experimenting using the average speed equation you learned i

astra-53 [7]

The average speed would be 33.29m/s.
The average speed equation is:

$Average speed = \frac{total distance}{total time}$

First you will need to solve for the distance you traveled in each scenario. So we can solve this by getting the product of speed and the time traveled.

Scenario 1:
Speed = 29m/s
Time = 120s
Distance = ?

Distance = (29m/s)(120s)
= 3,480m

Scenario 2
Speed = 35m/s
Time = 300s
Distance = ?

Distance = (35m/s)(300s)
= 10,500m

Now that you have the distance of both, you can solve for your average speed.

$Average speed = \frac{total distance}{total time}$
$= \frac{3,480m+10,500m}{120s+300s}$
$= \frac{13,980m}{420s}$
$= 33.29m/s$

5 0

3 years ago