Which of the following statements is true?

Find the impulse a 1500 kg car experiences slowing down from 40m/s to 10m/s?

Kitty [74]

Answer: - 45000 N.s

Explanation: Impulse is equal to the change in momentum

J = Δp

To solve for impulse we calculate the change in momentum

Δp = m ( Δv)

= 1500 kg ( 10 m/s - 40 m/s)

= - 45000 N.s

6 0

3 years ago

A test of the prototype of a new automobile shows that the minimum distance for a controlled stop from 95 km/h to zero is 55 m.

iris [78.8K]

Answer:

-0.64525g

Explanation:

t = Time taken for the car to stop

u = Initial velocity = 95 km/h

v = Final velocity = 0 km/h

s = Displacement

a = Acceleration

Equation of motion

$v^2-u^2=2as\\\Rightarrow a=\frac{v^2-u^2}{2s}\\\Rightarrow a=\frac{0^2-95^2}{2\times 0.055}\\\Rightarrow a=-82045.45\ km/h^2$

Converting to m/s²

$a=82045.45=\frac{82045.45\times 1000}{3600\times 3600}=-6.33\ m/s^2$

g = Acceleration due to gravity = 9.81 m/s²

Dividing both the accelerations, we get

$\frac{a}{g}=\frac{-6.33}{9.81}=-0.64525\\\Rightarrow a=-0.64525g$

Hence, acceleration of the car is -0.64525g

8 0

3 years ago

Because she had serious traffic accident on Friday the 13th of last month, Felicia is conceived that all Friday the 13th will br

elena-s [515]

Answer:

Illusory correlation

Explanation:

Illusory correlation is a psychological phenomenon of sensing a correlation or relationship between a particular quantity and other variables however unrelated the two variables may be. A person may establish such connections, which are indeed false connections, as a result of over emphasis on novel incidents that are easily noticed due to them being salient

For example, when a waiter at a restaurant is being rude to a person after the person was made to walk under a ladder due to ongoing construction.

4 0

2 years ago

A ball rolls across a floor with an acceleration of 0.100 m/s2 in a direction opposite to its velocity. The ball has a velocity

Westkost [7]

Answer:

4.15 m/s

Explanation:

Its given that acceleration is 0.1 m/s² with a direction opposite to the velocity. Since, the direction of acceleration is opposite to the velocity, this gives us a hint that the velocity is decreasing and so acceleration would be negative.

i.e.

acceleration = a = - 0.1 m/s²

Distance covered = S = 6m

Velocity after covering 6 meters = Final velocity = $v_{f}$ = 4 m/s

We need to find the initial speed, which will be the same as the magnitude of initial velocity.

Initial velocity = $v_{i}$ = ?

3rd equation of motion relates the acceleration, distance, final velocity and initial velocity as:

$2aS = (v_{f})^{2}-(v_{i})^{2}$

Using the known values in the formula, we get:

$2(-0.1)(6)=(4)^{2}- (v_{i})^{2}\\\\ (v_{i})^{2}=16+1.2\\\\ (v_{i})^{2}=17.2\\\\ v_{i}=4.15$

Thus, the initial speed of the ball was 4.15 m/s

3 0

3 years ago

As gravity continues to crush the inner core, the fusion of carbon and oxygen begins. What temperature is needed for the fusion

Olin [163]

Answer:

600,000,000 degree C

Explanation:

This stage is the last stage and is refereed to as supernova. In the beginning of this stage, gravity pulls the inner core and crush it, due to which fusion of atoms starts. Carbon and Oxygen fuse together and the temperature is about of 600,000,000 degree C.

The most heavier atom that can be formed out of this fusion is the iron. The moment all the atoms becomes of iron, no further fusion is possible hence that body emits radiation of high intensity and collapse causing a big supernova.

8 0

2 years ago