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Tju [1.3M]
2 years ago
7

The rock falls from the distance of 15 m before it hits the water. Calculate its kinetic energy just before hitting the water. S

how your working
Physics
2 answers:
yarga [219]2 years ago
7 0

Answer:

8.57m

Explanation:

v²=u²+2as

then1/2mv²

UkoKoshka [18]2 years ago
6 0

Answer:

k.e =  \frac{1}{2} m {v}^{2}  \\    {v}^{2}  =  {u}^{2}   +  2gs \\  {v}^{2}  = 0  + (2 \times 9.8 \times 15) \\ v = 17.1 \: m {s}^{ - 1}  \\ k.e =  \frac{1}{2}  \times m \times  {17.1}^{2}  \\  = 147m \: joules \\ m \: is \: mass

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Rudiy27

Answer:

6.7 × 10^{-2}

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2 years ago
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faltersainse [42]

Answer:

W = 5701 KW

Explanation:

From the question let inlet be labelled as point 1 and exit as point 2, for the fluid steam, we can get the following;

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Exit(2) : At saturated vapour; P2 = 0.8 bar and V2 = 150 m/s

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v2 = 2.087 m^(3)/kg

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Where AV is the volumetric flow rate.

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We also know energy equation could be defined as;

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Since the flow is adiabatic, potential energy can be taken to be zero. Therefore, we get;

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8 0
3 years ago
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