All categories

3 years ago

A school bus moves at speed of 35 mi/hr for 20 miles. How long will it take the bus to get to school

Physics

1 answer:

ludmilkaskok [199]3 years ago

6 0

Answer:

Explanation:

Assuming school is at the end of the 20 mile route, then

20 mi / 35 mi/hr = 0.57142...hr

which is about 34 minutes 17 seconds

You might be interested in

Different types of heat transfer: What is radiation?

denpristay [2]

The transfer of internal energy in the form of electromagnetic waves.

3 0

4 years ago

Two carts, one twice as heavy as the other, are at rest on a horizontal track. A person pushes each cart for 8 s. Ignoring frict

GalinKa [24]

Answer:

The correct option is: B that is 1/2 K

Explanation:

Given:

Two carts of different masses, same force were applied for same duration of time.

Mass of the lighter cart = $m$

Mass of the heavier cart = $2m$

We have to find the relationship between their kinetic energy:

Let the KE of cart having mass m be "K".

and KE of cart having mass m be "K1".

As it is given regarding Force and time so we have to bring in picture the concept of momentum Δp and find a relation with KE.

Numerical analysis.

⇒ $KE = \frac{mv^2}{2}$

⇒ $KE = \frac{mv^2}{2}\times \frac{m}{m}$

⇒ $KE = \frac{m^2v^2}{2}\times \frac{1}{m}$

⇒ $KE = \frac{(mv)^2}{2}\times \frac{1}{m}$

⇒ $KE = \frac{(\triangle p)^2}{2}\times \frac{1}{m}$

⇒ $KE = \frac{(\triangle p)^2}{2m}=\frac{(F\times t)^2}{2m}$

Now,

Kinetic energies and their ratios in terms of momentum or impulse.

KE (K) of mass m.

⇒ $K=\frac{(F\times t)^2}{2m}$ ...equation (i)

KE (K1) of mass 2m.

⇒ $K_1=\frac{(F\times t)^2}{2\times 2m}$

⇒ $K_1=\frac{(F\times t)^2}{4m}$ ...equation (ii)

Lets divide K1 and K to find the relationship between the two carts's KE.

⇒ $\frac{K_1}{K} =\frac{(F\times t)^2}{4m} \times \frac{2m}{(F\times t)^2}$

⇒ $\frac{K_1}{K} =\frac{2m}{4m}$

⇒ $\frac{K_1}{K} =\frac{2}{4}$

⇒ $\frac{K_1}{K} =\frac{1}{2}$

⇒ $K_1=\frac{K}{2}$

⇒ $K_1=\frac{1}{2}K$

The kinetic energy of the heavy cart after the push compared to the kinetic energy of the light cart is 1/2 K.

7 0

3 years ago

When the amplitudes of waves are equal, which frequency waves have the most energy?

Molodets [167]

Answer:

higher frequency waves will have more energy

Explanation:

5 0

2 years ago

How does energy transfer by waves differ from energy transfer by moving object

vodomira [7]

Energy transfer by waves: two primary modes = (electromagnetic waves, compression/transverse waves propagating through a medium)

1) electromagnetic waves:

Using a particle model for the wave (photons for light), energy transfer is similar to that by discrete moving object -- particles carry the energy from one place to another in the absence of a medium.

Energy delivery: discrete moving object uses inertia and momentum to transfer the energy from itself to the target. Photons are massless, so the energy delivery mechanism must be different.

2) compression/transverse waves propagating through a medium:

Energy passes through the medium with little to no net flow of the medium itself. In transverse water waves, when the energy wave passes by, to first order, the water particles move in vertical circular paths. This is different from energy transfer by a moving object in that the moving object must displace itself to the target position in order to deliver the energy -- resulting in a net flow of object material.

5 0

3 years ago

A hunter is aiming horizontally at a monkey who is sitting in a tree. The monkey is so terrified when it sees the gun that it fa

Dvinal [7]

Answer:a) The bullet will miss the monkey because the monkey falls down while the bullet speeds straight forward.

Explanation: The bullet keeps as it aim( the monkey) unless it is redirected by an external force that could redirect it. Hence, the bullet speeds straight forward.

3 0

3 years ago