A bomb, originally sitting at rest, explodes and during the

Which two labeled points on the fig are out of phase by 180° ?

GREYUIT [131]

You can use the points of answer:

B and F

5 0

3 years ago

Estimate the change in gravitational potential energy when a person with mass 80 kg rise from bed to a standing position. Assumi

Doss [256]

Answer:

change in gravitational potential energy Δ PE = 392 J

Explanation:

given data

mass of the person m = 80 kg

height of the centre of mass Δh = 0.50 m

to find out

change in gravitational potential energy

solution

we get here change in gravitational potential energy that is express here as

change in gravitational potential energy Δ PE = m × g × Δh .........1

put here value we get

change in gravitational potential energy Δ PE = m × g × Δh

change in gravitational potential energy Δ PE = 80 × 9.8 × 0.50

change in gravitational potential energy Δ PE = 392 J

7 0

3 years ago

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.

We have a formula for such condition,

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

where:

$\Delta T$ = temperature difference

Q= heat energy

m= mass of the body

c= specific heat of the body

Proving mathematically:

According to the given conditions

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

Zinc is best used for making a. glass b. walls c. screws d. fertilizers

Levart [38]

C. zinc is best used for making screws. Zinc is best used for making alloys, anything made from 55% or 95% copper more then likely contain zinc

5 0

4 years ago

The strings in a compound bow behave approximately like a

Pepsi [2]

The speed at which the arrow would be launched is 133.42 m/s

The work-energy theorem asserts that the net work done applied by the forces on a particular object is equivalent to the change in its kinetic energy.

The equation for the work-energy theorem can be computed as:

$\mathbf{W =\Delta K.E}$