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3 years ago

Show that the expression vf = vi + at is dimensionally correct

1 answer:

4 0

To show that the expression given is dimensionally correct, we can do a dimensional analysis where we write the units of each term in the expression.

vf [=] vi + at
m/s [=] m/s+ (m/s²) (s)
<span>m/s [=] m/s+ m/s
</span><span>m/s [=] m/s
</span>
Therefore, the expression is dimensionally correct.

You might be interested in

An object's buoyant force and weight mean the same thing.<br><br>A. True<br><br>B. False

german

Answer:

False

Explanation:

No. The buoyant force on an object is the portion of its weight that appears to vanish

when the object is in any fluid (could be either a liquid or a gas).

If the object happens to float in a particular fluid, then the buoyant force at that moment

is equal to the object's weight.

Notice that the buoyant force on an object will be different in different fluids.

6 0

2 years ago

A stone tied at one end of the string is whirled in vertical circle, where is the tension in the string be maximum and minimum?

Ber [7]

<h3>answer</h3>

The minimum velocity required for a object to rotate in a verticle plane is v

gr.

So, at bottom point, T

max

=mv

/r+mg=6mg.

At top-most point velocity is v

=gr.

So, T

min

=mv

/r−mg=0

So T

max

−T

min

=6mg=2×g⇒m=1/3 kg

4 0

3 years ago

shows a conical pendulum, in which the bob (the small object at the lower end of the cord) moves in a horizontal circle at const

Contact [7]

Answer:

a) $T=0.40 N$

b) $T=1.9 s$

Explanation:

Let's find the radius of the circumference first. We know that bob follows a circular path of circumference 0.94 m, it means that the perimeter is 0.94 m.

The perimeter of a circunference is:

$P=2\pi r=0.94$

$r=\frac{0.94}{2\pi}=0.15 m$

Now, we need to find the angle of the pendulum from vertical.

$tan(\alpha)=\frac{r}{L}=\frac{0.15}{0.90}=0.17$

$\alpha=9.44 ^{\circ}$

Let's apply Newton's second law to find the tension.

$\sum F=ma_{c}=m\omega^{2}r$

We use centripetal acceleration here, because we have a circular motion.

The vertical equation of motion will be:

$Tcos(\alpha)=mg$ (1)

The horizontal equation of motion will be:

$Tsin(\alpha)=m\omega^{2}r$ (2)

a) We can find T usinf the equation (1):

$T=\frac {mg}{cos(\alpha)}=\frac{0.04*9.81}{cos(9.44)}=0.40 N$

We can find the angular velocity (ω) from the equation (2):

$\omega=\sqrt{\frac{Tsin(\alpha)}{mr}}=3.31 rad/s$

b) We know that the period is T=2π/ω, therefore:

$T=\frac{2\pi}{\omega}=\frac{2\pi}{3.31}=1.9 s$

I hope it helps you!

8 0

2 years ago

Does a sled have inertia while sitting still

madam [21]

Answer:

Yes, a sled has inertia while sitting still.

Explanation:

From Newton's law of inertia, an object at rest will remain at rest unless it is acted upon by an external force. The reason the object will remain at rest unless an external force acts is because of inertia. Inertia means the resistance of an object to motion.

Thus, a sled hammer at rest will remain at rest unless it is acted upon by an external force. So we can conclude that it has Inertia.

7 0

3 years ago

Please write 4-5 sentences, please!! How would you describe the climate of Colorado? Find 1 piece of evidence from online to def

andreyandreev [35.5K]

Answer:

The climate in colorado is combination of high elevation, midlatitude, and continental interior geography results in a cool, dry, and invigorating climate. The average annual temperature for the state is 43.5 degrees Fahrenheit (F), which is 13.7 degrees below the global mean

Explanation:

4 0

2 years ago