A car that increase its speed from 20 km/h to 100 km/h undergoes -------acceleration,

Where have you heard the word calorie before what do you think a calorie is

Ainat [17]

Answer:

Explanation:

Calorie is a common term used to describe the amount of energy that can be derived from food products.

We quantify foods based on the calories of energy they possess. A high calorific food will yield more energy to the body and is often desired for intense physical activities.

Calorie is defined as the amount of heat energy needed to raise the temperature of 1g of a substance by 1°C.

Food calories slightly differs in definition and they imply the amount of heat needed to raise the temperature of 1kg of water by 1°C.

6 0

3 years ago

Kieran takes off from rest down a 50 m high, 10° slope on his jet-powered skis. The skis have a thrust of 280 N parallel to the

xz_007 [3.2K]

Answer:0.46

Explanation:

Given

Initial height $h=50 m$

inclination $\theta =10^{\circ}$

Thrust $=280 N$

combined mass of kieran and skis $m=50 kg$

Speed at the bottom $v=40 m/s$

From Work Energy Theorem

Work done by all the force is equal to change in kinetic Energy

$W_{gravity}+W_{friction}+W_{thrust}=\frac{1}{2}mv^2-0$ ------------1

distance traveled along the slope $x=\frac{50}{\sin 10}=287.93 m$

$W_{gravity}=mgh=50\times 9.8\times 50=24500 J$

$W_{thrust}=F\times x=280\times 287.93=80,620.4 J$

$W_{friction}=-\mu mg\cos 10$

substitute in 1

$24,500+80,620.4+W_{friction}=\frac{1}{2}\times 50\times 1600$

$W_{friction}=40,000-24,500-80,620.4$

$-\mu \cdot 50\times 9.8\times 287.93=-65,120.4$

$\mu =\frac{65,120.4}{141,085.7}=0.46$

8 0

2 years ago

(NO LINKS) A carpenter strikes a nail with a hammer, pushing it into wood.

Andrej [43]

Answer:

D, Im not very sure about this but I would say D

Explanation:

I tried

6 0

2 years ago

Are there conditions under which the incident light ray undergoes reflection but not transmission at the boundary? if so, then w

Luden [163]

Total internal reflection causes light to be completely reflected across the boundary between the two media but not transmitted.

<h3>What is total internal reflection?</h3>

The term total internal reflection occurs when light is moving from a denser to a less dense medium such as from glass to air. This phenomenon occurs at the interface between the two media.

There are two conditions necessary for total internal reflection and they are;

1) Light must travel from a denser to a less dense medium

2) The angle of incidence in the denser medium must be greater than the critical angle.

Total internal reflection causes light to be completely reflected across the boundary between the two media but not transmitted.

Learn more about total internal reflection:brainly.com/question/13088998

#SPJ1

6 0

1 year ago

Calculate the Latent Heat of Vaporization. (Please see picture attached)

Hunter-Best [27]

Answer:

20 J/g

Explanation:

In this question, we are required to determine the latent heat of vaporization

To answer the question, we need to ask ourselves the questions:

What is latent heat of vaporization?

It is the amount of heat required to change a substance from its liquid state to gaseous state without change in temperature.

It is the amount of heat absorbed by a substance as it boils.

How do we calculate the latent heat of vaporization?

Latent heat is calculated by dividing the amount of heat absorbed by the mass of the substance.

In this case;

Mass of the substance = 20 g
Heat absorbed as the substance boils is 400 J (1000 J - 600 J)

Thus,

Latent heat of vaporization = Quantity of Heat ÷ Mass

= 400 Joules ÷ 20 g

= 20 J/g

Thus, the latent heat of vaporization is 20 J/g

7 0

3 years ago