What can be found by counting the number of troughs per second in a wave diagram

El valor más preciso de la masa de un electron es 9.11*10^-11kg ¿ Cuánto aumentaría la masa de un cuerpo que se carga con -1 c d

chubhunter [2.5K]

Answer:

$m = 569.375\times 10^{6}\,kg$

Explanation:

Un electrón tiene una carga negativa de $1.6\times 10^{-19}\,C$ y la masa total es igual al producto del número de electrones y esa carga unitaria. El número de electrones se obtiene al dividir la carga total por la carga unitaria. (An electron has a negative charge of $1.6\times 10^{-19}\,C$ and the total mass is equal to the product of the qunatity of electrons and such unit charge. The quantity of electrons is found by diving the total charge by the unit charge):

$m = \frac{Q}{q} \cdot m_{e}$

$m = \left(\frac{1\,C}{1.6\times 10^{-19}\,C} \right)\cdot (9.11\times 10^{-11}\,kg)$

$m = 569.375\times 10^{6}\,kg$

7 0

3 years ago

A person kicks a ball, giving it an initial velocity of 20.0 m/s up a wooden ramp. When the ball reaches the top, it becomes air

Alex Ar [27]

Answer:

(a) Height is 4.47 m

(b) Height is 4.37 m

Solution:

As per the question:

Initial velocity of teh ball, $v_{o} = 20.0 m/s$

Angle made by the ramp, $\theta = 22.0^{\circ}$

Distance traveled by the ball on the ramp, d = 5.00 m

Now,

(a) At any point on the projectile before attaining maximum height, the velocity can be given by the eqn-3 of motion:

$v^{2} = v_{o}^{2} - 2gH$

where

H = $dsin22^{\circ} = 5sin22^{\circ}$

g = $9.8 m/s^{2}$

$v^{2} = 20^{2} - 2\times 9.8\times 5sin22^{\circ}$

$v = \sqrt{400 - 19.6\times 5sin22^{\circ}}$ = 19.06 m/s

Now, maximum height attained is given by:

$h = \frac{(vsin\theta)^{2}}{2g}$

$h = \frac{(19sin(22^{\circ}))^{2}}{2\times 9.8} = 2.60 m$

Height from the ground = $5sin22^{circ} + 2.86 = 1.87 + 2.60 = 4.47m$

(b) now, considering the coefficient of friction bhetween ramp and the ball, $\mu = 0.150$ :

velocity can be given by the eqn-3 of motion:

$v^{2} = v_{o}^{2} - 2gH - \mu gd$

$v^{2} = 20^{2} - 2\times 9.8\times 5sin22^{\circ} - 0.150\times 9.8\times 5$

$v = \sqrt{400 - 19.6\times 5sin22^{\circ} - 0.150\times 9.8\times 5}$ = 18.7 m/s

Now, maximum height attained is given by:

$h = \frac{(vsin\theta)^{2}}{2g}$

$h = \frac{(18.7sin(22^{\circ}))^{2}}{2\times 9.8} = 2.50 m$

Height from the ground = $5sin22^{circ} + 2.86 = 1.87 + 2.50 = 4.37 m$

6 0

3 years ago

A ball is dropped from a window and takes two seconds to reach the ground .it starts from rest and reaches a final speed of 20m/

Akimi4 [234]

The ball can't reach the speed of 20 m/s in two seconds, unless you THROW it down from the window with a little bit of initial speed. If you just drop it, then the highest speed it can have after two seconds is 19.6 m/s .

If an object starts from rest and its speed after 2 seconds is 20 m/s, then its acceleration is 20/2 = 10 m/s^2 .

(Gravity on Earth is only 9.8 m/s^2.)

3 0

3 years ago

While Newton's Second Law often deals with formulas and numerical calculations, there exist one very important nonnumerical conv

zheka24 [161]

Option B is the correct answer.

MKS system gives the following units:

Distance ----- meters

Mass ----- Kilograms

Time ----- seconds

meter is basic unit for length measurement. smaller units are centimeter, millimeter, micrometer, bigger units are kilometer and so on.

kilogram is the basic unit for mass. smaller unit is gram.

second is the basic unit for time. Greater units are minutes, hours, smallest unit are micro second and so on.