Техническое задание

What erases the impact craters on earth and is responsible for most of the landforms that we see?

frez [133]

The big bang theory I think

6 0

3 years ago

How many calories are needed to raise the temperature of 2g of water 3 C?

olga nikolaevna [1]

Answer:

The number of calories needed is 6c.

Explanation:

The amount of energy $Q$ needed to raise the temperature $\Delta T$ of water of mass $m$ is

$Q = mC\Delta T$

where $C = 1cal/g\cdot C$ is the specific heat capacity of water.

Putting in numbers into equation (1), we get:

$Q = (2g)(1)(3^oC )\\$

$\boxed{Q = 6\:cal }$

which is the number of calories needed.

8 0

4 years ago

an electron is released from rest in a region of space with a nonzero electric field.1. As the electron moves, does the electric

zvonat [6]

Answer:

1. a. increase

2. Because the electron has a negative charge its electric potential energy does not decrease as one might expect, but increases instead.

Explanation:

Lets first consider the relation between the electric field and electric potential.

E = -ΔV/Δs

As this equation indicates that the electric field is due to the change in potential and change in the the position of charge. Electric field is directed towards the decreasing potential and the electron moves in the opposite direction of the electric field where potential increases. Thats why the best explanation is that the electron has a negative charge it moves towards the positive region where the electric potential energy increases.

5 0

3 years ago

Michelle walked 217 meters in 2 minutes ,55 seconds what is her speed

anyanavicka [17]

Explanation:

55×60=3300

2×60=120

3300+120=3420

speed=distance/time

speed=3420/217

x=15.6ms^-1

8 0

2 years ago

. (a) How high a hill can a car coast up (engine disengaged) if work done by friction is negligible and its initial speed is 110

7nadin3 [17]

Answer:

(a) the high of a hill that car can coast up (engine disengaged) if work done by friction is negligible and its initial speed is 110 km/h is 47.6 m

(b) thermal energy was generated by friction is 1.88 x $10^{5}$ J

(C) the average force of friction if the hill has a slope 2.5º above the horizontal is 373 N

Explanation:

given information:

m = 750 kg

initial velocity, $v_{0}$ = 110 km/h = 110 x 1000/3600 = 30.6 m/s $\frac{30.6^{2} }{2x9.8}$

initial height, $h_{0}$ = 22 m

slope, θ = 2.5°

(a) How high a hill can a car coast up (engine disengaged) if work done by friction is negligible and its initial speed is 110 km/h?

according to conservation-energy

EP = EK

mgh = $\frac{1}{2} mv_{0} ^{2}$

gh = $\frac{1}{2} v_{0} ^{2}$

h = $\frac{v_{0} ^{2} }{2g}$

= 47.6 m

(b) If, in actuality, a 750-kg car with an initial speed of 110 km/h is observed to coast up a hill to a height 22.0 m above its starting point, how much thermal energy was generated by friction?

thermal energy = mgΔh

= mg (h - $h_{0}$ )

= 750 x 9.8 x (47.6 - 22)

= 188160 Joule

= 1.88 x $10^{5}$ J

(c) What is the average force of friction if the hill has a slope 2.5º above the horizontal?

f d = mgΔh

f = mgΔh / d,

where h = d sin θ, d = h/sinθ

therefore

f = (mgΔh) / (h/sinθ)

= 1.88 x $10^{5}$ /(22/sin 2.5°)

= 373 N

8 0

3 years ago