What is matter made of ?

A roller-coaster track has six semicircular "dips" with different radii of curvature. The same roller-coaster cart rides through

inessss [21]

Answer:

E > A = B > C > D

Explanation:

On a semicircular curve, the magnitude of force is given by the formula as :

$F=\dfrac{mv^2}{r}$

Here, m is the mass of the vehicle

Case A : R = 60 m v = 16 m/s

$F_1=\dfrac{m(16)^2}{60}=4.27m\ N$

Case B : R = 15 m v = 8 m/s

$F_2=\dfrac{m(8)^2}{15}=4.27m\ N$

Case C : R = 30 m v = 4 m/s

$F_3=\dfrac{m(4)^2}{30}=0.534m\ N$

Case D : R = 45 m v = 4 m/s

$F_4=\dfrac{m(4)^2}{45}=0.356m\ N$

Case E : R = 30 m v = 16 m/s

$F_5=\dfrac{m(16)^2}{30}=8.53m\ N$

The order of the magnitude of the force of the roller-coaster track on the cart from largest to smallest is :

E > A = B > C > D

6 0

3 years ago

A 150 g ball and a 240 g ball are connected by a 33-cm-long, massless, rigid rod. The balls rotate about their center of mass at

stira [4]

Answer:

v= 3.18 m/s

Explanation:

Given that

m= 150 g = 0.15 kg

M= 240 g = 0.24 kg

Angular speed ,ω = 150 rpm

The speed in rad/s

$\omega =\dfrac{2\pi N}{60}$

$\omega =\dfrac{2\pi \times 150}{60}$

ω = 15.7 rad/s

The distance of center of mass from 150 g

$r=\dfrac{150\times 0+240\times 33}{150+240}\ cm$

r= 20.30 cm

The speed of the mass 150 g

v= ω r

v= 20.30 x 15.7 cm/s

v= 318.71 cm/s

v= 3.18 m/s

6 0

3 years ago

Two balls have masses 18 kg and 47 kg. The 18 kg ball has an initial velocity of 76 m/s (to the right) along a line joining the

BigorU [14]

Answer:

The final velocity of 18 kg ball is $V_{2}$ = 42.09 $\frac{m}{sec}$

Explanation:

Mass of first ball $m_{1}$ = 18 kg

Mass of second ball $m_{2}$ = 47 kg

Initial velocity of 18 kg ball $V_{1}$ = 76 $\frac{m}{sec}$

Initial velocity of 47 kg ball = 0

Final velocity of 18 kg ball $V_{2}$ = ??

Final velocity of 18 kg ball is given by the formula

$V_{2}$ = $\frac{2 m_{1} V_{1} }{m_{1} + m_{2} }$

Put all the values in above formula we get

$V_{2}$ = 2 × 18 × $\frac{76}{65}$

$V_{2}$ = 42.09 $\frac{m}{sec}$

Thus, the final velocity of 18 kg ball is $V_{2}$ = 42.09 $\frac{m}{sec}$

3 0

3 years ago

A laser used for many applications of hard surface dental work emits 2780-nm wavelength pulses of variable energy (0-300 mJ) abo

Bess [88]

Answer:

a

$n = 1.119 *10^{18} \ photons$

b

$P = 1.6 \ W$

Explanation:

From the question we are told that

The wavelength is $\lambda = 2780 nm = 2780 *10^{-9} \ m$

The energy is $E = 80 mJ = 80 *10^{-3} \ J$

This energy is mathematically represented as

$E = \frac{n * h * c }{\lambda }$

Where c is the speed of light with a value $c = 3.0 *10^{8} \ m/s$

h is the Planck's constant with the value $h = 6.626 *10^{-34} \ J \cdot s$

n is the number of pulses

So

$n = \frac{E * \lambda }{h * c }$

substituting values

$n = \frac{80 *10^{-3} * 2780 *10^{-9}}{6.626 *10^{-34} * 3.0 *10^{8} }$

$n = 1.119 *10^{18} \ photons$

Given that the pulses where emitted 20 times in one second then the period of the pulse is

$T = \frac{1}{20}$

$T = 0.05 \ s$

Hence the average power of photons in one 80-mJ pulse during 1 s is mathematically represented as

$P = \frac{E}{T}$

substituting values

$P = \frac{ 80 *10^{-3}}{0.05}$

$P = 1.6 \ W$

6 0

4 years ago

Once you start pulling your object with less force than friction, what should you expect your object to do? What about when your

forsale [732]

#Case -1

If Pulling force is less than frictional force the object won't move .

#Case-2

If Pulling force is greater than frictional force then object will be .

In order to calculate friction force you need Limiting friction first .

$\\ \sf\longmapsto F_L=\mu sN$

u s is coefficient of static friction and N is normal reaction

Or

$\\ \sf\longmapsto F_L=\mu smg$

As N=mg

8 0

3 years ago

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What is matter made of ?​

What is matter made of ?