NEED HELP ASAP PLEASE

eduard

Answer:

Wave A.

Explanation:

The energy of a wave is directly proportional to the square of the amplitude.

If a wave has higher amplitude, it will have more energy. On the other hand, a wave having lower amplitude, it will have less eenergy.

In this case, we need to tell which wave has higher energy. Hence, the correct option is A because it has a higher amplitude.

8 0

3 years ago

Read 2 more answers

The static frictional force between a 95-kilogram object and the floor is 45 Newtons. The kinetic frictional force is only 22 Ne

Lisa [10]

Answer:

F = 69.5 [N]

Explanation:

We must remember that the friction force is defined as the product of the normal force by the coefficient of friction, and it can be calculated by the following expression.

$f=N*miu$

where:

N = normal force [N]

miu = friction coefficient

f = friction force = 22 [N]

Now we must calculate the force exerted by means of Newton's second law which tells us that the sum of forces on a body is equal to the product of mass by acceleration.

$F - f = m*a$

where:

F = force exerted [N]

f = friction force [N]

m = mass = 95 [kg]

a = acceleration = 0.5 [m/s²]

Now replacing:

$F - 22 = 95*0.5\\F = 47.5 + 22\\F = 69.5 [N]$

6 0

3 years ago

a student calculates experimentally the value of density of an iron as 4.4 gcm³. if the actual density of an iron is 7.6 gcm³, c

ser-zykov [4K]

Hola!

Percentage Error is a measurement of the discrepancy between an observed and a true, or accepted value.

[ refer the attachment. ]

According to Question,

% error = $\frac{7.4 - 7.6}{7.6}$ × 100

= 2.631 % = 2.7 % (approximately.)

hope it helps!

5 0

3 years ago

I just need a full answer here not only so I can answer the question, but also so that I can learn.

Xelga [282]

Answer: Number of valence electrons determine how fast or easy for an atom to gain stability. Either by gaining electrons or by losing electrons.

Group one and seven elements react fast because they only have one electron to gain or lose.

Explanation:

Number of valence electrons tell us the number of electrons an atom will gain or lose in order to attain stability in electron configuration.

All the elements in a particular group will have the same number of valence electrons as follows:

Group one - 1 valence electron

Group two - 2 valence electrons

Group three - 3 valence electrons

Group four - 4 valence electrons

Group five - 3 valence electrons

Group six - 2 valence electrons

Group seven - 1 valence electron

Group eight - 0 valence electron

Some elements are more reactive than the others because of the electron affinity, oxidation state and electronegativity of the atoms

For instance, elements in group 7 are more reactive than others because of their oxidation state and they have very high electronegativity.

Also, group one elements are more reactive because they only have one electron to loose.

7 0

3 years ago

Compute the size of the charge necessary for two spheres separated by 1m to be attached with the force of 1N. How many electrons

yarga [219]

Answer:

$q\approx 6.6\cdot 10^{13}~electrons$

Explanation:

<u>Coulomb's Law</u>

The force between two charged particles of charges q1 and q2 separated by a distance d is given by the Coulomb's Law formula:

$\displaystyle F=k\frac{q_1q_2}{d^2}$

Where:

$k=9\cdot 10^9\ N.m^2/c^2$

q1, q2 = the objects' charge

d= The distance between the objects

We know both charges are identical, i.e. q1=q2=q. This reduces the formula to:

$\displaystyle F=k\frac{q^2}{d^2}$

Since we know the force F=1 N and the distance d=1 m, let's find the common charge of the spheres solving for q:

$\displaystyle q=\sqrt{\frac{F}{k}}\cdot d$

Substituting values:

$\displaystyle q=\sqrt{\frac{1}{9\cdot 10^9}}\cdot 1$

$q = 1.05\cdot 10^{-5}~c$

This charge corresponds to a number of electrons given by the elementary charge of the electron:

$q_e=1.6 \cdot 10^{-19}~c$

Thus, the charge of any of the spheres is:

$\displaystyle q = \frac{1.05\cdot 10^{-5}~c}{1.6 \cdot 10^{-19}~c}$

$\mathbf{q\approx 6.6\cdot 10^{13}~electrons}$

5 0

2 years ago