What element on the periodic table has 31 protons and 37 neutrons?

A particle moves along a straight line and its position at time t is given by

Alisiya [41]

(A) Use interval notation to indicate the time interval or union of time intervals when the particle is moving forward and backward

the particle is speeding up

if a(t) >0, it means 12t-48>0, and t >4, I = ]4, infinity[

the particle is speeding down

if a(t) < 0, it means 12t-48>0, and t < 4, I = ] -infinity, 4[

when the particle is moving forward and backward

that is depending of the sign of v(t)

moving forward if v(t)> 0

moving backward if v(t)< 0

but v(t) = 6t² - 48 t +90, this quadratic equation has exactly two solutions, t =1, and t =3

so after taking care the sign of 6t² - 48 t +90,

v(t)> o when t is in I = ] –inf, 1[ U ]4, inf[,the particle is moving forward

v(t) < o when t is in I = ]1, 4[,the particle is moving backward

3 0

3 years ago

The Hi line of the Balmer series is emitted in the transition from n = 3 to n = 2. Compute the wavelength of this line for l H a

irina1246 [14]

Answer:

$\lambda=550\ nm$

Explanation:

The Hi line of the Balmer series is emitted in the transition from n = 3 to n = 2 i.e. $n_i=3$ and $n_f=2$

The wavelength of Hi line of the Balmer series is given by :

$\dfrac{1}{\lambda}=R(\dfrac{1}{n_f}-\dfrac{1}{n_i})$

$\dfrac{1}{\lambda}=1.09\times 10^7\times (\dfrac{1}{2}-\dfrac{1}{3})$

$\lambda=5.50\times 10^{-7}\ m$

$\lambda=550\ nm$

So, the wavelength for this line is 550 nm. Hence, this is the required solution.

6 0

3 years ago

If the resistance in a circuit remains constant, what happens to the electric power when the current increases?

Elena L [17]

V=IR (voltage equals current times resistance). So if the voltage increases, then the current increases provided that the resistance remains constant.

4 0

3 years ago

Read 2 more answers

For two objects with masses 100 kg and 500 kg to be 20 meters apart , find the gravity between them

Vikki [24]

Answer:

8,3375*10^-9 N

Explanation:

4 0

3 years ago

For a projectile launched horizontally, which of the following best describes the downward component of a projectile's velocity?

Angelina_Jolie [31]

C. The downward component of the projectile's velocity continually increases

Explanation:

The motion of a projectile consists of two independent motions:

- A uniform motion (with constant velocity) along the horizontal direction

- A uniformly accelerated motion, with constant acceleration (equal to the acceleration of gravity) in the downward direction

Here we want to study the downward component of the projectile's velocity. Since the vertical motion is a uniformly accelerated motion, the vertical velocity is given by:

$v=u+at$