Answer:
The mass of the ice block is equal to 70.15 kg
Explanation:
The data for this exercise are as follows:
F=90 N
insignificant friction force
x=13 m
t=4.5 s
m=?
applying the equation of rectilinear motion we have:
x = xo + vot + at^2/2
where xo = initial distance =0
vo=initial velocity = 0
a is the acceleration
therefore the equation is:
x = at^2/2
Clearing a:
a=2x/t^2=(2x13)/(4.5^2)=1.283 m/s^2
we use Newton's second law to calculate the mass of the ice block:
F=ma
m=F/a = 90/1.283=70.15 kg
When the object is at the focal point the angular magnification is 2.94.
Angular magnification:
The ratio of the angle subtended at the eye by the image formed by an optical instrument to that subtended at the eye by the object when not viewed through the instrument.
Here we have to find the angular magnification when the object is at the focal point.
Focal length = 6.00 cm
Formula to calculate angular magnification:
Angular magnification = 25/f
= 25/ 8.5
= 2.94
Therefore the angular magnification of this thin lens is 2.94
To know more about angular magnification refer:: brainly.com/question/28325488
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Explanation:
It is given that, the position of a particle as as function of time t is given by :
Let v is the velocity of the particle. Velocity of an object is given by :
![v=\dfrac{d[(8t+9)i+(2t^2-8)j+6tk]}{dt}](https://tex.z-dn.net/?f=v%3D%5Cdfrac%7Bd%5B%288t%2B9%29i%2B%282t%5E2-8%29j%2B6tk%5D%7D%7Bdt%7D)
So, the above equation is the velocity vector.
Let a is the acceleration of the particle. Acceleration of an object is given by :
![a=\dfrac{d[8i+4tj+6k]}{dt}](https://tex.z-dn.net/?f=a%3D%5Cdfrac%7Bd%5B8i%2B4tj%2B6k%5D%7D%7Bdt%7D)
At t = 0, 
Hence, this is the required solution.
Answer:
a.73.3%
b.26.6%
Explanation:
a. The efficiency is the energy output, divided by the energy input, and expressed as a percentage.
#Given the energy input as 1500J and the subsequent output as 1100J, the TV's efficiency is calculated as:
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Hence, the TV has an efficiency of 33.3%
b. From a above, we know that the TV has an output of 1100J and input of 1500J.
-We therefore calculate it's wastage as the difference between output and input:
<em>Wastage=Energy Input-Energy Output=1500J-1400J=400J</em>
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Hence, the TV has wasted of 26.6%
<h3><u>Answer;</u></h3>
A compound which is a pure substance
<h3><u>Explanation;</u></h3>
- <em><u>A pure substance is a substance with a definite and constant composition and distinct chemical properties. Pure substance can either be a compound or an element.</u></em>
- <em><u>Compound is a substance made of two or more elements that can be broken down by chemical means. therefore, Chemical reaction is the only way to separate a compound into its elements</u></em>
- Element on the other hand is a pure substance that is composed of only one type of atom. Unlike compounds pure substances can not be broken down by chemical means.
