Mercury is in the 80th position in the periodic table. How many protons does it have?

Help me with the question in the image I provided

inna [77]

Answer: 10 s, 30 m/s , 150 m

Explanation:

Given

The speed of motorcyclist is $u_1=15\ m/s$

The initial speed of a police motorcycle is $u_2=0\ m/s$

acceleration of police motorcycle is $a=3\ m/s^2$

Police will catch the motorcyclist when they traveled equal distances

distance traveled by motorcyclist in time t is

$\Rightarrow s_1=15\times t$

Distance traveled by Police in time t is

$\Rightarrow s_2=u_2t+\frac{1}{2}at^2\\\Rightarrow s_2=0+0.5\times 3\times t^2$

put $s_1=s_2$

$\Rightarrow 15t=0.5\times 3\times t^2\\\\\Rightarrow t(1.5t-15)=0\\\\\Rightarrow t=\dfrac{15}{1.5}=10\ s$

Police officer's speed at that time is

$\Rightarrow v_2=u_2+at\\\Rightarrow v_2=0+3\times 10=30\ m/s$

Distance traveled by each vehicle is

$\Rightarrow s_1=s_2=15\times t=15\times 10=150\ m$

8 0

2 years ago

True or False:<br><br> It is safe to touch an electric current while soaking wet.

olganol [36]

Answer:

False

Explanation:

Water contains ions that can conduct electricity and if touched it can cause harm (aka electrocution).

8 0

2 years ago

Convert 68852 millijoules into Calories. (Write your answer in the decimal form. Do not include units in your answer).

alex41 [277]

Answer: 68852 millijoules = 16.46 calories

Explanation:

Given;

Convert 68852 millijoules to calories.

1 calorie = 4.184J = 4184millijoules

Therefore,

1 millijoule = 1/4184 calories

68852 millijoule = 68852 × 1/4184 calories

= 16.46 calories

6 0

2 years ago

As you move away from a positive charge distribution, the electric field:

GalinKa [24]

Answer:

The electric field always decreases.

Explanation:

The electric field due to a point charge is given by :

$E=\dfrac{kq}{r^2}$

Where

k = electric constant

q = charge

r = distance from the charge

It is clear from the above equation that as the distance from the charge particle increases the electric field decreases. As you move away from a positive charge distribution, the electric field always decreases. Hence, the correct option is (c) "Always decreases".

3 0

2 years ago

The displacement vector A and B when added together , give the resultant vector R so that R= A+B use the data in the drawing and

Salsk061 [2.6K]

The addition of vectors involve both magnitude and direction. In this case, we make use of a triangle to visualize the problem. The length of two sides were given while the measure of the angle between the two sides can be derived. We then assign variables for each of the given quantities.

Let:

b = length of one side = 8 m
c = length of one side = 6 m
A = angle between b and c = 90°-25° = 75°

We then use the cosine law to find the length of the unknown side. The cosine law results to the formula: a^2 = b^2 + c^2 -2*b*c*cos(A). Substituting the values, we then have: a = sqrt[(8)^2 + (6)^2 -2(8)(6)cos(75°)]. Finally, we have a = 8.6691 m.

Next, we make use of the sine law to get the angle, B, which is opposite to the side B. The sine law results to the formula: sin(A)/a = sin(B)/b and consequently, sin(75)/8.6691 = sin(B)/8. We then get B = 63.0464°. However, the direction of the resultant vector is given by the angle Θ which is Θ = 90° - 63.0464° = 26.9536°.

In summary, the resultant vector has a magnitude of 8.6691 m and it makes an angle equal to 26.9536° with the x-axis.

5 0

2 years ago