In the reaction 2Ca + O2 → 2CaO for every 2 Ca you will need how much O2?

When energy is converted from one form to another in a chemical or physical change, which of the following also changes by a mea

ArbitrLikvidat [17]

Answer:

None of the above

Explanation:

When energy is converted from one form to another in a chemical or physical change, none will change. This is due to the law of conservation of energy. It states that the total energy of the system remains constant. It only changes energy from one form of energy to another. So, the correct option is (d) "none of the above".

3 0

3 years ago

A solid block, with a mass of 0.15kg, on a frictionless surface is pushed directly onto a horizontal spring, with a spring const

iren [92.7K]

Answer:

16.1 m/s

Explanation:

We can solve the problem by using the law of conservation of energy.

At the beginning, the spring is compressed by x = 35 cm = 0.35 m, and it stores an elastic potential energy given by

$U=\frac{1}{2}kx^2$

where k = 316 N/m is the spring constant. Once the block is released, the spring returns to its natural length and all its elastic potential energy is converted into kinetic energy of the block (which starts moving). This kinetic energy is equal to

$K=\frac{1}{2}mv^2$

where m = 0.15 kg is the mass of the block and v is its speed.

Since the energy must be conserved, we can equate the initial elastic energy of the spring to the final kinetic energy of the block, and from the equation we obtain we can find the speed of the block:

$\frac{1}{2}kx^2=\frac{1}{2}mv^2\\v=\sqrt{\frac{kx^2}{m}}=\sqrt{\frac{(316 N/m)(0.35 m)^2}{0.15 kg}}=16.1 m/s$

4 0

3 years ago

A student performs this experiment and measures the bar to have a mass of 150g and length of 36cm. What is the moment of inertia

Ugo [173]

Answer:

The moment of inertia of the bar is $45\times10^{-4}\ kg-m^2$

Explanation:

Given that,

mass of bar = 150 g

Length l = 36 cm

We need to calculate the moment of inertia of the bar

Using formula of moment inertia

$I=\dfrac{1}{12}Ml^2$

Where,

M = mass of the bar

L = length of the bar

Put the value into the formula

$I=\dfrac{1}{12}\times150\times10^-3\times36\times10^{-2}$

$I=45\times10^{-4}\ kg-m^2$

Hence, The moment of inertia of the bar is $45\times10^{-4}\ kg-m^2$

4 0

4 years ago

Describe a situation in which an object's speed is constant but its velocity is changing.

Olegator [25]

1) If the object changes directions with the same speed, it will be changing its velocity, because velocity is a vector, which depends on both magnitude and direction. Speed is just magnitude regardless of direction.

2) Rotational motion.

5 0

3 years ago

. Find the buoyant force exerted on a ball with radius of 2 meters, when the ball is entirely immersed in the water.

almond37 [142]

Explanation:

Buoyancy force is equal to the weight of the displaced fluid:

B = ρVg

where ρ is the density of the fluid,

V is the volume of the displaced fluid,

and g is the acceleration due to gravity.

The fluid is water, so ρ = 1000 kg/m³.

The volume displaced is that of a sphere with radius 2 m:

V = 4/3 π r³

V = 4/3 π (2 m)³

V ≈ 33.5 m³

The buoyancy force is therefore:

B = (1000 kg/m³) (33.5 m³) (9.8 m/s²)

B ≈ 328,400 N

Round as needed.

8 0

3 years ago