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3 years ago

4. A car, initially traveling east with a speed of

Physics

1 answer:

PilotLPTM [1.2K]3 years ago

5 0

Answer:

150 m

Explanation:

Given,

u=5m/s

a=2m/s2

t=10s

v=?

s=?

Now,

v=u+at

=5+2×10

=5+20

=25m/s

So,

s=u+v/2×t

=5+25/2×10

=30/2×10

=15×10

=150m

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$Q = c \cdot m \cdot \Delta T$ ,

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$\begin{aligned}\Delta T &= T(\text{final}) - T(\text{initial}) \\ &= (0\; \rm ^\circ C) - (-10\; \rm ^\circ C) \\ &= 10\; \rm K\end{aligned}$ .

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$\begin{aligned}\Delta T &= T(\text{final}) - T(\text{initial}) \\ &= (10\; \rm ^\circ C) - (0\; \rm ^\circ C) \\ &= 10\; \rm K\end{aligned}$ .

Calculate the energy required to achieve that temperature change:

$\begin{aligned}Q_3&= c(\text{water}) \cdot m(\text{water}) \cdot \Delta T\\ &= 4200\; \rm J \cdot kg \cdot K^{-1} \\ &\quad\quad \times 0.100\; \rm kg \times 10\; \rm K\\ &= 4.20\times 10^{3}\; \rm J\end{aligned}$ .

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Find the sum of these three parts of energy:

$\begin{aligned}Q &= Q_1 + Q_2 + Q_3 = 3.99\times 10^{4}\; \rm J\end{aligned}$ .

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