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SCORPION-xisa [38]
3 years ago
13

Why do some scientists not use controlled experiments?

Physics
1 answer:
Leviafan [203]3 years ago
7 0
Observational studies are a prime example. Observational data is more reflective of the real environments that scientists make their inferences to than controlled experiments. The disadvantage of observational studies is that the variability is far greater. <span />
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Solution A has a specific heat of 2.0 J/g◦C. Solution B has a specific heat of 3.8 J/g◦C. If equal masses of both solutions start
fgiga [73]

Answer: 2. Solution A attains a higher temperature.

Explanation: Specific heat simply means, that amount of heat which is when supplied to a unit mass of a substance will raise its temperature by 1°C.

In the given situation we have equal masses of two solutions A & B, out of which A has lower specific heat which means that a unit mass of solution A requires lesser energy to raise its temperature by 1°C than the solution B.

Since, the masses of both the solutions are same and equal heat is supplied to both, the proportional condition will follow.

<em>We have a formula for such condition,</em>

Q=m.c.\Delta T.....................................(1)

where:

  • \Delta T= temperature difference
  • Q= heat energy
  • m= mass of the body
  • c= specific heat of the body

<u>Proving mathematically:</u>

<em>According to the given conditions</em>

  • we have equal masses of two solutions A & B, i.e. m_A=m_B
  • equal heat is supplied to both the solutions, i.e. Q_A=Q_B
  • specific heat of solution A, c_{A}=2.0 J.g^{-1} .\degree C^{-1}
  • specific heat of solution B, c_{B}=3.8 J.g^{-1} .\degree C^{-1}
  • \Delta T_A & \Delta T_B are the change in temperatures of the respective solutions.

Now, putting the above values

Q_A=Q_B

m_A.c_A. \Delta T_A=m_B.c_B . \Delta T_B\\\\2.0\times \Delta T_A=3.8 \times \Delta T_B\\\\ \Delta T_A=\frac{3.8}{2.0}\times \Delta T_B\\\\\\\frac{\Delta T_{A}}{\Delta T_{B}} = \frac{3.8}{2.0}>1

Which proves that solution A attains a higher temperature than solution B.

7 0
3 years ago
SYW A force of 175 N is needed to keep a stationary engine of weight 640 N on wooden skids from
grigory [225]

Answer:

phle follow karo yrr tab hee bat u ga

4 0
3 years ago
Read 2 more answers
A 200.0 kg piano is elevated by a crane to a height of 10.0 meters above a sidewalk. If the rope holding the piano breaks, what
Nitella [24]
All that business about the crane and the rope and the falling
is only there to confuse us.

The piano ended up 5 meters above the ground.

           Potential energy = (mass) (gravity) (height)

                                   = (200 kg) (9.81 m/s²) (5 m)

                                   = (200 · 9.81 · 5)  (kg-m²/s²)

                                   =   9,810 joules   . 
5 0
2 years ago
Please help asap
posledela

Answer:

A

Explanation:

the object's mass determines the speed of the object and its kinetic energy

4 0
2 years ago
Read 2 more answers
In a two-body collision, if the momentum of the system is conserved, then which of the
lakkis [162]

Answer:

c) may also be conserved

Explanation:

Momentum is conserved  in both elastic and inelastic type of collisions.

But the differences is that:

In an ELASTIC type of collisions, KINETIC ENERGY IS ALSO CONSERVED.

whereas, In an INELASTIC type of collision, KINETIC ENERGY IS NOT CONSERVED.

So unless until type of collision is specified, we can not say anything about the conservation of kinetic energy after collision.

Hence, may also be conserved is the appropriate option here.

5 0
2 years ago
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