All categories

3 years ago

Determine the time needed for the load at b to attain a speed of 10 m/s, starting from rest.

1 answer:

5 0

Unfortunately, I can't give a definite answer because I only know two information: the initial velocity which is 0 because it is at rest, and the final velocity which is 10 m/s. To solve this, I should know one other information to determine time. It could be the constant acceleration. The useful equation to be used is:

a = (vf - v₀)/t

So, assuming that the object was dropped from a certain height, the acceleration is due to gravity which is equal to 9.81 m/s². Then,

9.81 = (10 - 0)/t
t = 1.02 seconds

You might be interested in

A sealed test tube traps 25.0 cm3 of air at a pressure of 1.00 atm and temperature of 18°C. The test tube’s stopper has a diamet

puteri [66]

Answer:

180° C

Explanation:

First we start by finding the area of the stopper.

A = πd²/4, where d = 1.5 cm = 0.015 m

A = 3.142 * 0.015² * ¼

A = 1.767*10^-4 m²

Next we find the force on the stopper

F = (P - P•)A, where

F = 10 N

P = pressure inside the tube,

P• = 1 atm

10 = (P - 101325) * 1.767*10^-4

P - 101325 = 10/1.767*10^-4

P - 101325 = 56593

P = 56593 + 101325

P = 157918 Pascal

Now, remember, in an ideal gas,

P1V1/T1 = P2V2/T2, where V is constant, then we have

P1/T1 = P2/T2, and when we substitute the values, we have

101325/(273 + 18) = 157918/ T2

101325/291 = 157918/ T2

T2 = (157918 * 291)/101325

T2 = 453 K

T2 = 453 - 273 = 180° C

3 0

4 years ago

The closest star to our solar system is Alpha Centauri, which is 4.12 × 10^16 m away. How long would it take light from Alpha Ce

bonufazy [111]

Time = (distance) / (speed)

Time = (4.12x10^16 m) / (3 x10^8 m/s)

Time = 1.37 x 10^8 seconds

Divide the seconds by 86,400 to get days. Then divide the days by 365 to get years.

Time = about 4.35 years

4 0

3 years ago

An electron in a cathode-ray beam passes between 2.5cm long parallel-plate electrodes that are 6.0mm apart. A 2.1mT, 2.5-cm-wide

Dmitry_Shevchenko [17]

Answer:

(a). The speed of electron is $1.56\times10^{7}\ m/s$ .

(b). The radius of electron is $4.2\ cm$

Explanation:

Given that,

Length = 2.5 cm

Distance = 6.0 mm

Magnetic field = 2.1 T

Potential difference = 700 V

(a). We need to calculate the electron's speed

Using formula of speed

$v=\sqrt{\dfrac{2eV}{m}}$

Put the value into the formula

$v=\sqrt{\dfrac{2\times1.6\times10^{-19}\times700}{9.1\times10^{-31}}}$

$v=15689290.81\ m/s$

$v=1.56\times10^{7}\ m/s$

(b). We need to calculate the radius of electron

Using formula of centripetal force

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

$r=\dfrac{mv}{qB}$

Where,

m = mass of electron

v = speed of electron

r = radius

q = charge of electron

B = magnetic field

Put the value into the formula

$r=\dfrac{9.1\times10^{-31}\times1.56\times10^{7}}{1.6\times10^{-19}\times2.1\times10^{-3}}$

$r=0.042\ m$

$r=4.2\ cm$

Hence, (a). The speed of electron is $1.56\times10^{7}\ m/s$ .

(b). The radius of electron is 4.2 cm

8 0

3 years ago

A polonium isotope with an atomic mass of 211.988868 u undergoes alpha decay, resulting in a daughter isotope with an atomic mas

prisoha [69]

Answer:

K = 9.53 MeV

Explanation:

The kinetic energy that the alpha particle has emitted, is the energy in excess after removing the resting energy of the atoms and the helium nucleus that forms the alpha particle

Since energy and masses are related and cannot be

m₀ c² = $m_{f}$ c² + m_He c²+ K

K = c² (m₀ - m_{f} - m_He)

the mass of the Helium atom is 4 u

K = (3 10⁸)² (211,988868 -207.976652 - 4,002) 1,661 10⁻²⁷

K = 14,949 10⁻¹¹ (0.0102)

K = 1,527 10⁻¹² J

let's reduce 1 J = 6,242 10¹² MeV

K = 9.53 MeV

7 0

4 years ago

A marble, a bowling ball, a basketball, and a baseball are rolling across the floor at 1.0 m/s. Which one has the greatest kinet

sveticcg [70]

Answer: A Bowling Ball

Explanation:

A body possess kinetic energy due to virtue of its motion. It depends on the mass of the body and the speed with which it is travelling.

K.E = 0.5 mv²

K.E. ∝ m

It is given that the marble, bowling ball, basketball and baseball all are rolling with the same speed. This means that the greatest energy would be possessed by the body having greatest mass.

On an average the mass of a marble is about 50 g, mass of a bowling ball is 750 g, mass of baseball is 150 g and mass of basketball is 600 g. Since the mass of a Bowling ball is the greatest, it would possess the greatest kinetic energy.

3 0

3 years ago

Read 2 more answers