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4 years ago

In the periodic table notation below what information does the number 40.08 tell you

Physics

1 answer:

tia_tia [17]4 years ago

5 0

Answer:

The number above the symbol is the atomic mass (or atomic weight). This is the total number of protons and neutrons in an atom. The number below the symbol is the atomic number and this reflects the number of protons in the nucleus of each element's atom. Every element has a unique atomic number.

Explanation:

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A circuit with a 60 V battery, a 7 Ω resistor, a resistor with 0.2 A across it, and another 7 Ω resistor in series. What is the

skelet666 [1.2K]

Answer:

28.6 ohm

Explanation:

there is a 3rd resistor in series. voltage drop across the resistors will be equal to 60v

7*.2+7*.2 +.2x = 60

2.8+.2x = 60

.2x = 57.2

x = 28.6

8 0

2 years ago

A student rubs a rubber balloon on their hair for several seconds. The student then rubs a second rubber balloon on her hair for

erastovalidia [21]

Answer:

Option A

Explanation:

In this experiment, when balloon is rubbed on the chair electrons are transferred from the hair to the surface of the balloon thereby making balloon negatively charged and hair positively charged. When two negatively charged balloon are brought close to each other, they repel while when balloon is brought closer to the hair, they attract each other

Hence, option A is correct

7 0

3 years ago

A charge q is at the point x = 5.0 m , y = 0. Write expressions for the unit vectors you would use in Coulomb's law if you were

Flauer [41]

Answer:

A) $\^r = \^y$

B) $\^r = -\^x$

C) $\^r = -0.14\^x + 0.99\^y$

Explanation:

Coulomb's Law is

$\vec{F}_{ab} = K\frac{q_1q_2}{r^2}\^r$

where r is the distance between the two point charges.

The question clearly asks the unit vector expressions of the force that q exerts on the other charge. So, we do not need to find the force, but only the distance vector, r, between charges, and then we can derive the unit vector pointing only the direction of the force.

A) $\vec{r} = \vec{r}_b - \vec{r}_a = (5\^x + \^y) - (5\^x + 0) = \^y\\\^r = \frac{\vec{r}}{|\vec{r}|} = \frac{\^y}{1} = \^y$

B) $\vec{r} = \vec{r}_b - \vec{r}_a = (0 + 0) - (5\^x + 0) = -5\^x\\\^r = \frac{\vec{r}}{|\vec{r}|} = \frac{-5\^x}{5} = -\^x$

C) $\vec{r} = \vec{r}_b - \vec{r}_a = (4.5\^x + 3.5\^y) - (5\^x + 0) = -0.5\^x + 3.5\^y\\\^r = \frac{\vec{r}}{|\vec{r}|} = \frac{-0.5\^x + 3.5\^y}{\sqrt{(0.5)^2+(3.5)^2}} = \frac{-0.5\^x + 3.5\^y}{3.53} = -0.14\^x + 0.99\^y$

7 0

3 years ago

Read 2 more answers

600 kg elephant runs at 5 m/s and jumpts onto a 100kg cart. If the coefficient of friction is .04 how far will the cart travel o

Minchanka [31]

Answer:

Eleven seconds.

Explanation:

Two keys are needed to solve this problem. First, the conservation of momentum: allowing you to calculate the cart's speed after the elephant jumped onto it. It holds that:

$m_ev_e+m_c\cdot0=(m_e+m_c)v_0\implies \\v_0=\frac{m_ev_e}{m_e+m_c}=\frac{600kg\cdot 5\frac{m}{s}}{700kg}=4.29\frac{m}{s}$

So, once loaded with an elephant, the cart was moving with a speed of 4.29m/s.

The second key is the kinematic equation for accelerated motion. There is one force acting on the cart, namely friction. The friction acts in the opposite direction to the horizontal direction of the velocity v0, its magnitude and the corresponding deceleration are:

$F_r = 0.04\cdot (m_e+m_c)g\implies a_r = 0.04\cdot g= 0.04 \cdot 9.8 \frac{m}{s^2}=0.39\frac{m}{s^2}$