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In the absence of air, why does the horizontal component of velocity for a projectile remain constant while the vertical compone

Crazy boy [7]

Because there is no horizontal force on the object, and we all know what happens to velocity in a direction where there is no force.

5 0

3 years ago

You can hear someone around the corner before you can see them due to reflection, diffraction, refraction, or absorption?

Irina-Kira [14]

The answer to this is reflection, because the sound waves are reflected off of the walls

7 0

3 years ago

I need help on this science

Serga [27]

Ok ok ok ok ok ok ok ok ok

8 0

3 years ago

A 4.3 kg steel ball and 6.5 m cord of negligible mass make up a simple pendulum that can pivot without friction about the point

Alekssandra [29.7K]

Answer

given,

mass of steel ball, M = 4.3 kg

length of the chord, L = 6.5 m

mass of the block, m = 4.3 Kg

coefficient of friction, μ = 0.9

acceleration due to gravity, g = 9.81 m/s²

here the potential energy of the bob is converted into kinetic energy

$m g L = \dfrac{1}{2} mv^2$

$v= \sqrt{2gL}$

$v= \sqrt{2\times 9.8\times 6.5}$

v = 11.29 m/s

As the collision is elastic the velocity of the block is same as that of bob.

now,

work done by the friction force = kinetic energy of the block

$f . d = \dfrac{1}{2} mv^2$

$\mu m g. d = \dfrac{1}{2} mv^2$

$d=\dfrac{v^2}{2\mu g}$

$d=\dfrac{11.29^2}{2\times 0.9 \times 9.8}$

d = 7.23 m

the distance traveled by the block will be equal to 7.23 m.

8 0

3 years ago

A 1kg cart slams into a stationary 1kg cart at 2 m/s. The carts stick together and move forward at a speed of 1 m/sl. Determine

finlep [7]

Answer:

No, it is not conserved

Explanation:

Let's calculate the total kinetic energy before the collision and compare it with the total kinetic energy after the collision.

The total kinetic energy before the collision is:

$K_i = K_1 + K_2 = \frac{1}{2}mv_1^2 + \frac{1}{2}mv_2^2=\frac{1}{2}(1 kg)(2 m/s)^2+\frac{1}{2}(1 kg)(0)^2=2 J$

where m1 = m2 = 1 kg are the masses of the two carts, v1=2 m/s is the speed of the first cart, and where v2=0 is the speed of the second cart, which is zero because it is stationary.

After the collision, the two carts stick together with same speed v=1 m/s; their total kinetic energy is

$K_f = \frac{1}{2}(m_1+m_2)v^2=\frac{1}{2}(1 kg+1kg)(1 m/s)^2=1 J$

So, we see that the kinetic energy was not conserved, because the initial kinetic energy was 2 J while the final kinetic energy is 1 J. This means that this is an inelastic collision, in which only the total momentum is conserved. This loss of kinetic energy does not violate the law of conservation of energy: in fact, the energy lost has simply been converted into another form of energy, such as heat, during the collision.

3 0

3 years ago