Hy would you expect sodium (Na) to react strongly with chlorine (Cl)?

schepotkina [342]

Answer:

B. $2Li(s) + ZnSO_{4} (aq) -> Li_{2}SO_{4} (aq) +Zn(s)$

Explanation:

The answer choice B. is a double displacement reaction. A double displacement reaction is where there were two compounds reacting.

8 0

3 years ago

As outlaws escape in their getaway ear, which goes 3/4 c, the police officer fires a bullet from a pursuit ear, which only goes

Mariulka [41]

Answer:

a) Bullet will hit

b) Bullets will not hit

Explanation:

Given:

The velocity of the bullet, u = $\frac{1}{3}c$ in the rest frame of the bullet pursuit car

The velocity of the original frame of reference, v = $-\frac{1}{2}c$ with respect to the pursuit car.

Now, according to the Galileo

the velocity of the bullet in the original frame of reference (u') will be

u' = u - v

on substituting the values we get

u' = $\frac{1}{3}c-(-\frac{1}{2}c)$

or

u' = $\frac{1}{3}c+\frac{1}{2}c$

or

u' = $\frac{5}{6}c$

since this velocity ( $\frac{5}{6}c$ ) is greater than the ( $\frac{3}{4}c$ )

hence,

<u>the bullet will hit</u>

Now, according to the Einstein theory

the velocity of the bullet in the original frame of reference (u') will be

$u'=\frac{u-v}{1-\frac{uv}{c^2}}$

on substituting the values we get

$u'=\frac{\frac{1}{3}c-\frac{1}{2}c}{1-\frac{\frac{1}{3}c\times \frac{1}{2}c}{c^2}}$

or

$u'=\frac{\frac{5}{6}c}{1-\frac{1}{6}}$

or

$u'=\frac{5}{7}c$

since,

$u'=\frac{5}{7}c$ is less than ( $\frac{3}{4}c$ ), this means that the bullet will not hit

7 0

4 years ago

The Global Positioning System (GPS) is a constellation of about 24 artificial satellites. The GPS satellites are uniformly distr

Liono4ka [1.6K]

Answer:

b) 3.72m/s²

c) 9.33*10^5

d) 9.33*10^5

e) 11.85 hrs

Explanation:

a) to confirm that gEarth is about 98 m/s².

Let's use the formula:

$gEarth= \frac{G*M}{R^2}$

$= \frac{6.67*10^-^1^1*5.972*10^2^4}{(6378*10^3)^2}$

= 9.78 m/s²

=> 9.8m/s²

b) Given:

$m = 6.417*10^2^3$

r = 2106 miles

$g_Mars = \frac{G*M}{R^2}$

$= \frac{6.67*10^-^1^1*6.417*10^2^3}{(2106*1.61*10^3)^2}$

=3.72 m/s²

c) we use:

$F = \frac{G*M*m}{R^2}$

$=\frac{6.67*10^-^1^1*5.972*10^2^4*1630*10^3}{((20000+6378)*10^3)^2}$

$= 9.33*10^5 N$

d) Let's take the force of gravitybon earth due to satellite as our answer in (c) because the Earth's gravitational force on a GPS satellite and the force of gravity on a GPS satellite on earth are equal and opposite (two mutual forces).

$F = 9.33*10^5 N$

e) In a circular motion,

Gravitional force = Centripetal force.

$\frac{GM*m}{R^2}=\frac{m*v^2}{R}$

$\frac{GM}{R}= v^2$

Solving for v, we have

$v= \sqrt{\frac{6*67*10^-^1^1*5.972*10^2^4}{(20000+6278)*10^3}}$

v = 3886m/s

Therefore,

v = 2πR/T

$3886 = \frac{2*pi*(20000+6378)*10^3}{T}$

Solving for T, we have:

T = 42650seconds

Convert T to hours

T = 42650/60*60

T = 11.86hrs

6 0

4 years ago

What is the energy of a 4kg apple that is sitting on a 2 m high tree branch?

miv72 [106K]

78.4 joules is the energy of a 4 kg apple that is sitting on a 2 m high tree branch.

<u>Explanation: </u>

When an apple falls to the ground from a tree, its positional energy (stored as potential gravitational energy) turns into kinetic energy, during a fall. Chemical potential energy is chemical energy because it is food and potential energy as it can still have ability to move. So, in the given case, kinetic energy is zero.

To find potential energy, the formula would be

$\text { potential energy }(P . E)=m \times g \times h$

Where, given

m – Mass – 4 kg

$g-\text { Earth'sgravity }-9.8 \mathrm{m} / \mathrm{s}^{2}$ (Known value)

h – Height - 2 m

Substitute these values, we get

$P . E=4 \times 9.8 \times 2=78.4 \text { joules }$

8 0

3 years ago

Explain why the duster accelerates different rates when different surfaces are in contact with the track

vichka [17]

Answer:

Because on different surfaces there's more/less friction. Smooth surfaces will allow the duster to accelerate while rough surfaces will decrease the acceleration.

8 0

3 years ago

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