How can the conversion from potential energy to kinetic energy provide energy that is useful to people

All electromagnetic waves travel at the same speed in a vacuum, usually referred to as the speed of light. This speed is approxi

natali 33 [55]

Answer:

The following formula is used to calculate the speed or velocity of a wave. V = f * w Where V is the velocity (m/s) f is the frequency (hz)

4 0

2 years ago

Which acide will have more strength out of two acids of pH value 2 and 5 why

gladu [14]

Ph 2 will ahve more strength due to the fact that its more acidic compared to pH 5.

the lower the number of a pH, the more it is heading towards being acidic, but the higher the number, the more it heads towards being an alkali. here is a ppt i made along time ago. hope it can help you . have a nice day

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5 0

2 years ago

1) The heat of combustion for the gases hydrogen, methane and ethane are −285.8, −890.4 and −1559.9 kJ/mol respectively at 298K.

Morgarella [4.7K]

Answer:

The enthalpy of the reaction is 64.9 kJ/mol.

Explanation:

$H_2 + \frac{1}{2}O_2\rightarrow H_2O,\Delta H_1 =-285.8 kJ$ ..[1]

$CH_4 + 2O_2\rightarrow CO_2 + 2H_2O,\Delta H_2 =-890.4 kJ$ ..[2]

$C_2H_6 + \frac{7}{2}O_2\rightarrow 2CO_2 + 3H_2O,\Delta H_3= -1559.9 kJ$ ..[3]

$2CH_4(g)\rightarrow C_2H_6(g) + H_2(g),\Delta H_4=?$ ..[4]

2 × [2] - [1]- [3] = [4] (Using Hess's law)

$\Delta H_4=2\times \Delta H_2 -\Delta H_1 -\Delta H_3$

$\Delta H_4=2\times (-890.4 kJ)-(-285.8 kJ) -(-1559.9 kJ)$

$\Delta H_4=64.9 kJ/mol$

The enthalpy of the reaction is 64.9 kJ/mol.

3 0

2 years ago

A force of 30 N is applied to a screwdriver to pry the lid off of a can of paint. The screwdriver applies 75 N of force to the l

Ipatiy [6.2K]

The formula of mechanical advantage in this situation is:
MA = Input Force ÷ Output Force

The input force is the 30N applied to a screwdriver while the output force is the 75N force to the lid.

So,

MA = 30N/75N
MA = 0.40

Hence the mechanical advantage of the screwdriver is 0.40.

7 0

2 years ago

A runner wants to run 13.1 km . She knows that her running pace is 6.2 mi/h .How many minutes must she run? Hint: Use 6.2 mi/h a

frutty [35]

Answer:

79 minutes

Explanation:

1) Convert the distance, 13.1 km to miles

Conversion factor:

1 = 1 mi / 1.61 km

13.1 km [ 1 mi / 1.61 km ] = 8.1336 mi

2) Use 6.2 mi/h as a converstion factor between distance and time

8.1366 mi × 1 / [6.2 mi/h] = 1.3124 h

3) Convert 1.3124 h to minutes

1.3124 h × [ 60 min/h] = 78.7 min

Rounding to the nearest minutes (two significant figures):

79 min ← answer

4 0

2 years ago