A crate of mass 50kg is pushed along a floor with a force of 20N for a distance of

Which letter represents the wavelength of the wave?

Evgesh-ka [11]

The greek letter λ (lamda) is used to represent the wavelength of the wave.

6 0

3 years ago

Which of the following BEST summarizes the relationship between groups and culture and critical thinking?

slamgirl [31]

Answer:

Groups and culture helps in influencing our values,ethics and beliefs. This influence should always be questioned through the process of thinking critically.

This best summarizes the relationship between groups and culture and critical thinking.

6 0

3 years ago

Which of the following are characteristics of good experimental design? Check all that apply.

miv72 [106K]

Answer:

The correct answer will be-

1. Allows scientists to replicate experiments

2. Tests only one variable at a time

3. Plans how to record data so they can be published

Explanation:

A scientific experiment is performed to test the hypothesis which represents the limited explanation of the phenomenon.

The experiment is designed in a way that it test one variable at a time like the growth of plants. The experiment must be designed in a way that it can be replicated to reduce the error and repeated by other scientific persons to support the experiment. The design includes the plan for recording the results as it is one of the steps of the scientific method.

Thus, the selected options are the correct answer.

Controlled experiment is the type of experiment that involves changing only one variable at a time. Controlled experiment is subtly defined as an experiment which holds everything constant except one particular variable. This type of experiment allows only one variable to ever change at a given time

5 0

3 years ago

Read 2 more answers

3. What is the potential energy of a 8 Newton book sitting on a shelf that is 12 meters high?

Svetradugi [14.3K]

Answer:

P = 96 J

Explanation:

Given that,

Weight of the book, W = mg = 8 N

It is placed at a height of 12 m

We need to find the potential energy of the book. The potential energy of an object is given by the formula as follows :

E = mgh

mg = Weight

$E=8\ N\times 12\ m\\E=96\ J$

So, the potential energy of the book is 96 J.

8 0

4 years ago

assume that the initial speed is 25 m/s and the angle of projection is 53 degree above the hroizontal. the cannon ball leaves th

finlep [7]

Answer:

A. xmax = 131.49 m

B. t = 8.74 s

C. ymax = 220.33 m

Explanation:

A. In order to find the horizontal distance which cannon travels you first calculate the flight time. The flight time can be calculated by using the following formula:

$y=y_o+v_osin\theta-\frac{1}{2}gt^2$ (1)

yo: height from the projectile is fired = 200m

vo: initial velocity of the projectile = 25m/s

g: gravitational acceleration = 9.8 m/s^2

θ: angle between the direction of the initial motion of the ball and the horizontal = 53°

t: time

You need the value of t when the projectile hits the ground. Then, in th equation (1) you make y = 0m.

When you replace the values of all parameters in the equation (1), you obtain the following quadratic formula:

$0=200+(25)sin53\°t-\frac{1}{2}(9.8)t^2\\\\0=200+19.96t-4.9t^2$ (2)

You use the quadratic formula to obtain the value of t:

$t_{1,2}=\frac{-19.96\pm\sqrt{(19.96)^2-4(-4.9)(200)}}{2(-4.9)}\\\\t_{1,2}=\frac{-19.96\pm65.71}{-9.8}\\\\t_1=8.74s\\\\t_2=-4.66s$

You use the positive value because it has physical meaning.

Now, you can calculate the horizontal range of the projectile by using the following formula:

$x_{max}=v_ocos\theta t$

$x_{max}=(25m/s)(cos53\°)(8.74s)=131.49m$

The cannon ball travels a horizontal distance of 131.49 m

B. The cannon ball reaches the canon for t = 8.74s

C. The maximum height is obtained by using the following formula:

$y_{max}=y_o+\frac{v_o^2sin^2\theta}{2g}$ (3)

By replacing in the equation (3) the values of all parameters you obtain:

$y_{max}=200m+\frac{(25m/s)^2(sin53\°)^2}{2(9.8m/s^2)}\\\\y_{mac}=200m+20.33m=220.33m$

The maximum height reached by the cannon ball is 220.33m

3 0

3 years ago