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3 years ago

John pushes his brother Danny on a skateboard. John applies a force of 29 N and Danny's acceleration is 0.4 m/s

Physics

2 answers:

belka [17]3 years ago

4 0

Answer:

Explanation:

Mumz [18]3 years ago

4 0

Answer:

The combined mass of Danny and his skateboard = m = 72.5 kg

Explanation:

Force applied by john = F = 29N

Danny’s Acceleration = a = 0.4 m/s

Combined mass of Danny and his skateboard = m = ?

According to Newton’s second law of motion:

F = ma

m = F/a

m = 29/0.4

m = 72.5 kg

Hence, the combined mass of Danny and his skateboard will be 72.5 Kg.

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The period of a mechanical wave is 5 seconds. what is the frequency of the wave?

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Read 2 more answers

A glass windowpane in a home is 0.62 cm thick and has dimen- sions of 1.0 m 3 2.0 m. On a certain day, the indoor temper- ature

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Answer:

Explanation:

Thermal conductivity of glass pane = .8 W / m K

For conduction of heat , the formula is as follows

Q = $\frac{kA(T_1 - T_2 )t}{d }$ ; Q is heat conducted in time t by a medium of thickness d , area of cross section A and ( T₁ - T₂ ) is the temperature difference .

Putting the values in the equation

Q = $\frac{.8 \times32\times(25 - 0 )\times1}{.0062 }$

= 103225.8 W

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3 years ago