Ask question

Ask question

All categories

3 years ago

6

A car having an initial velocity of 12 meters per second speed up uniformly to 22 meters per second. This change is made in 4 se

cond. What is the car's acceleration? Show solution

1 answer:

Sonbull [250]3 years ago

7 0

(22-12)/4

10/4

2.5 meters per second sqaured

You might be interested in

Light of wavelength 597 nm falls on a double slit, and the first bright fringe of the interference pattern is seen at an angle o

Kazeer [188]

Answer:

2.2 µm

Explanation:

For constructive interference, the expression is:

$d\times sin\theta=m\times \lambda$

Where, m = 1, 2, .....

d is the distance between the slits.

Given wavelength = 597 nm

Angle, $\theta$ = 15.8°

First bright fringe means , m = 1

So,

$d\times sin\ 15.8^0=1\times \597\ nm$

$d\times 0.2723=1\times \597\ nm$

$d=2192.43481\ nm$

Also,

1 nm = 10⁻⁹ m

1 µm = 10⁻⁶ m

So,

1 nm = 10⁻³ nm

Thus,

<u>Distance between slits ≅ 2.2 µm</u>

8 0

2 years ago

Read 2 more answers

All ions are atoms with a what?

irina1246 [14]

Answer is D. Neutral charge

6 0

2 years ago

Describe the main reason why the scientific community did not accept Alfred wegener idea of continental drift?

lara31 [8.8K]

<span>I think they were also too skeptic to believe the continent did move or pull apart, even today do you believe that the continents broke from one big flat plate, and that they pulled apart? They also wonder what large force would be responsible for the movement.

It was much later that evidences from plant and animal features that had similarity from two different planets came up that scientists began accepting the idea of continental drift.
And similar rock strata from two different opposite continents, showed similar rock strata.
All these evidences came up much later after Alfred Wengener.

So Alfred Wengener was honored Posthumously</span>

7 0

3 years ago

child slides down a snow‑covered slope on a sled. At the top of the slope, her mother gives her a push to start her off with a s

Strike441 [17]

Answer:

θ = 13.7º

Explanation:

According to the work-energy theorem, the change in the kinetic energy of the combined mass of the child and the sled, is equal to the total work done on the object by external forces.
The external forces capable to do work on the combination of child +sled, are the friction force (opposing to the displacement), and the component of the weight parallel to the slide.
As this last work is just equal to the change in the gravitational potential energy (with opposite sign) , we can write the following equation:

$\Delta K + \Delta U = W_{nc} (1)$

ΔK, is the change in kinetic energy, as follows:

$\Delta K = \frac{1}{2}* m* (v_{f} ^{2} - v_{0} ^{2}) (2)$

ΔU, is the change in the gravitational potential energy.
If we choose as our zero reference level, the bottom of the slope, the change in gravitational potential energy will be as follows:

$\Delta U = 0 - m*g*h = -m*g*d* sin\theta (3)$

Finally, the work done for non-conservative forces, is the work done by the friction force, along the slope, as follows:

$W_{nc} = F_{f} * d * cos 180\º \\\\ = 0.2*m*g*d* cos 180\º = -0.2*m*g*d (4)$

Replacing (2), (3), and (4) in (1), simplifying common terms, and rearranging, we have:

$\frac{1}{2}* (v_{f} ^{2} - v_{0} ^{2}) = g*d* sin\theta -0.2*g*d$

Replacing by the givens and the knowns, we can solve for sin θ, as follows: $\frac{1}{2}*( (4.30 m/s) ^{2} - (0.75 m/s)^{2}) = 9.8 m/s2*25.5m* sin\theta -0.2*9.8m/s2*25.5m\\ \\ 8.56 (m/s)2 = 250(m/s)2* sin \theta -50 (m/s)2\\ \\ sin \theta = \frac{58.6 (m/s)2}{250 (m/s)2} = 0.236$ ⇒ θ = sin⁻¹ (0.236) = 13.7º

8 0

2 years ago

To a stationary, a bus moves south with a speed of 15 m/s. a man inside walks toward the front of the bus with a speed of 0.2 m/

marta [7]

It is 15.2 m/s South.

8 0

2 years ago

Read 2 more answers