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2 years ago

3. Imagine a 10kg block moving with a speed of 20m/s calculate the kinetic energy of this block

1 answer:

6 0

The formula of the kinetic energy is:
$E_{k} = \frac{m v^{2} }{2}$
where m is a mass of the object, v is speed of the object at the moment of time. So we have:
$E_{k} = \frac{10* 20^{2} }{2} = 2000J$
The answer is 2000 Joules.

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Does heat demagnetize?

Nastasia [14]

Answer:

Yes

Explanation:

Heat affects the magnets because it confuses and misaligns the magnetic domains, causing magnetism to decrease

3 0

2 years ago

The angle between the two force of magnitude 20N and 15N is 60 degrees (20N force being horizontal) determine the resultant in m

BARSIC [14]

A) The resultant force is 30.4 N at $25.3^{\circ}$

B) The resultant force is 18.7 N at $43.9^{\circ}$

Explanation:

In order to find the resultant of the two forces, we must resolve each force along the x- and y- direction, and then add the components along each direction to find the components of the resultant.

The two forces are:

$F_1 = 20 N$ at $0^{\circ}$ above x-axis

$F_2 = 15 N$ at $60^{\circ}$ above y-axis

Resolving each force:

$F_{1x}=F_1 cos \theta = (20)(cos 0)=20 N\\F_{1y}=F_1 sin \theta =(20)(sin 0)=0 N$

$F_{2x}=F_2 cos \theta = (15)(cos 60)=7.5 N\\F_{2y}=F_2 sin \theta =(15)(sin 60)=13.0 N$

So, the components of the resultant are:

$F_x = F_{1x}+F_{2x}=20+7.5 = 27.5 N\\F_y = F_{1y}+F_{2y}=0+13.0=13.0 N$

And the magnitude of the resultant is:

$F=\sqrt{F_x^2+F_y^2}=\sqrt{27.5^2+13.0^2}=30.4 N$

And the direction is:

$\theta=tan^{-1}(\frac{F_y}{F_x})=tan^{-1}(\frac{13.0}{27.5})=25.3^{\circ}$

In this case, the 15 N is applied in the opposite direction to the 20 N force. Therefore we need to re-calculate its components, keeping in mind that the angle of the 15 N force this time is

$\theta=180^{\circ}-60^{\circ}=120^{\circ}$

So we have:

$F_{2x}=F_2 cos \theta = (15)(cos 120)=-7.5 N\\F_{2y}=F_2 sin \theta =(15)(sin 120)=13.0 N$

So, the components of the resultant this time are:

$F_x = F_{1x}+F_{2x}=20-7.5 = 12.5 N\\F_y = F_{1y}+F_{2y}=0+13.0=13.0 N$

And the magnitude is:

$F=\sqrt{F_x^2+F_y^2}=\sqrt{13.5^2+13.0^2}=18.7 N$

And the direction is:

$\theta=tan^{-1}(\frac{F_y}{F_x})=tan^{-1}(\frac{13.0}{13.5})=43.9^{\circ}$

Learn more about vector addition:

brainly.com/question/4945130

brainly.com/question/5892298

#LearnwithBrainly

7 0

2 years ago

Why is an earthworm an invertebrate?

zimovet [89]

Earthworm have bones Some children confuse earthworms, which are invertebrates and have no bones, with snakes which are vertebrates and do have a bony skeleton and many ribs.

8 0

2 years ago

Read 2 more answers

A wheel is used to turn a valve stem on a water valve. How much is the mechanical advantage when an effort of 80 lbs. is applied

Ann [662]

Answer:

Explanation:

From the question given above, the following data were obtained:

Effort (E) = 80 lbs

Load (L) = 320 lbs

Mechanical advantage (MA) =?

Mechanical advantage is simply defined as the ratio of load to effort. Mathematically, it is expressed as:

Mechanical advantage = Load / Effort

MA = L / E

With the above formula, we can obtain the mechanical advantage as illustrated below:

Effort (E) = 80 lbs

Load (L) = 320 lbs

Mechanical advantage (MA) =?

MA = L / E

MA = 320 / 80

MA = 4

Thus, the mechanical advantage is 4

3 0

2 years ago

Dinosaurs’ skeletons can be distinguished from those of other reptiles by the structure of the hips and legs.

jeyben [28]

True, they had a hole in their hip socket that allowed them to run faster than other reptiles of their size at the time. As well as most reptiles besides reptiles had legs to the side, rather than under them like dinosaurs did.

Hope this helps!

5 0

3 years ago