1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
mixer [17]
3 years ago
10

A car that is traveling in a straight line at 40 km/h can brake to a stop within 20 m. If the same car is traveling at 120 km/h

what would be its stopping distance in this case? Assume the braking force is the same in both cases and ignore air resistance.
Physics
1 answer:
stiks02 [169]3 years ago
8 0

Answer:

180 m

Explanation:

Case 1.

U = 40 km/h = 11.1 m/s, V = 0, s = 20 m

Let a be the acceleration.

Use third equation of motion

V^2 = u^2 + 2 as

0 = 11.1 × 11.1 - 2 × a × 20

a = 3.08 m/s^2

Case 2.

U = 220 km/h = 33.3 m/s, V = 0

a = 3.08 m/s^2

Let the stopping distance be x.

Again use third equation of motion

0 = 33.3 × 33.3 - 2 × 3.08 × x

X = 180 m

You might be interested in
In the diagram below, a 5 kg box is pushed from rest by an applied force of 15N for 22 seconds. What was the impulse caused by t
Yakvenalex [24]

Answer:

330Ns

Explanation:

Given parameters:

Mass of the box  = 5kg

Initial velocity  = 0m/s

Force applied  = 15N

Time  = 22s

Unknown:

Impulse  = ?

Final momentum  = ?

Solution:

The impulse of the box can be determined using the expression below:

     Impulse  = Force x time

    Impulse  = 15 x 22 = 330Ns

The final momentum is the same as this impulse

The impulse and the final momentum is 330Ns

4 0
3 years ago
In the design of a supermarket, there are to be several ramps connecting different parts of the store. Customers will have to pu
tatuchka [14]

Answer:

3.90 degrees

Explanation:

Let g= 9.81 m/s2. The gravity of the 30kg grocery cart is

W = mg = 30*9.81 = 294.3 N

This gravity is split into 2 components on the ramp, 1 parallel and the other perpendicular to the ramp.

We can calculate the parallel one since it's the one that affects the force required to push up

F = WsinΘ

Since customer would not complain if the force is no more than 20N

F = 20

294.3sin\theta = 20

sin\theta = 20/294.3 = 0.068

\theta = sin^{-1}0.068 = 0.068 rad = 0.068*180/\pi \approx 3.90^0

So the ramp cannot be larger than 3.9 degrees

6 0
3 years ago
Calculate frequency if wavelength is 35 m and wave speed is 546 m/s.
adoni [48]
The answer to your question is a 25.6 HZ
6 0
3 years ago
Compare the foot of mollusks with the tube feet of echinoderms.
stira [4]

Mollusks live in fresh water, in marine environment, but also on land.

<span>Echinoderms live only in water. This is the reason why they have developed different systems for moving. Mollusks have only singular muskullus foot for walking and Echinoderms have tube feet which they use for moving, as well for collecting and transporting food to their mouth. </span>



4 0
3 years ago
Estimate the mass of blood in your body Explain your reasoning (Note: It is not enough to provide a numeric answer. The main poi
AVprozaik [17]

Answer: A little more that 5 Kg for a healthy person

Explanation: First, we know the following:

The regular adult has from 9 to 12 pints of blood. This is around 5 liters for a healthy male adult.

The human body is composed mostly on water, around 80%.

Blood is mostly composed on plasma, which makes blood thicker than water.

Knowing that, almost all the body is compose of water, it is safe to think that blood density should be near to that of water but higher.

The density on water is a know value. Which makes the following true:

<em>1 Liter of Water weights 1 Kg</em>

<em />

It could be said then, that the total mass of blood for a healthy person should be a little more that 5 kgs.

4 0
2 years ago
Other questions:
  • I'm in  my lab, writing an essay about the properties of Bose Einstein Condensate. I forgot the formula of producing the condens
    13·1 answer
  • A satellite is held in orbit by a 2000- N gravitational
    8·1 answer
  • A soccer player hits a ball with a velocity of 22 m/s at an angle of 36.9 above the horizontal. Air resistance can be ignored. a
    14·1 answer
  • You are sliding across a hockey rink and catch a hockey puck as you continue to slide. What type of collision is this?
    5·2 answers
  • How Fast Is Lightning?
    12·1 answer
  • Under some circumstances, a star can collapse into an extremely dense object made mostly of neutrons and called a neutron star.
    11·1 answer
  • A(n) 712 kg elevator starts from rest. It moves upward for 3.13 s with a constant acceleration until it reaches its cruising spe
    6·1 answer
  • How does a smoother surface affect braking distance
    8·1 answer
  • Voltage is 50v and capacitance is 30c what is the charge<br>​
    5·1 answer
  • If a car drives 10 miles NE and then due East for 10 minutes traveling 8
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!