Answer:
126000 J
Explanation:
Applying,
Q = cm(t₂-t₁).................. Equation 1
Where Q = Amount of heat, c = specifc heat capacity of water, m = mass of water, t₁ = Initial temperature, t₂ = Final temperature.
From the question,
Given: m = 2 kg, t₁ = 25°C, t₂ = 40°C
Constant: c = 4200 J/kg.°C
Substitute these value into equation 1
Q = 2×4200(40-25)
Q = 2×4200×15
Q = 126000 J
a) The kinetic energy (KE) of an object is expressed as the product of half of the mass (m) of the object and the square of its velocity (v²):
![KE = \frac{1}{2}m* v^{2}](https://tex.z-dn.net/?f=KE%20%3D%20%5Cfrac%7B1%7D%7B2%7Dm%2A%20v%5E%7B2%7D%20)
It is given:
v = 8.5 m/s
m = 91 kg
So:
![KE= \frac{1}{2}*91*8.5^{2} =3,287.4J](https://tex.z-dn.net/?f=KE%3D%20%5Cfrac%7B1%7D%7B2%7D%2A91%2A8.5%5E%7B2%7D%20%3D3%2C287.4J)
b) We can calculate height by using the formula for potential energy (PE):
PE = m*g*h
In this case, h is eight, and PE is the same as KE:
PE = KE = 3,287.4 J
m = 91 kg
g = 9.81 m/s² - gravitational acceleration
h = ? - height
Now, let's replace those:
3,287.4= 91 * 9.81 * h
⇒ h = 3,287.4/(91*9.81) = 3,287.4/892.7 = 3.7 m
A book falls to the floor.
A car skids to a stop.
A foam ball launches from a spring (Are the right answer, just did this one 4:34 pm Jan/21/19)
The instantaneous velocity always tangential to circular path and instantaneous acceleration always points towards the center of circle.
What is instantaneous?
The definition of instantaneous velocity is the rate of change of location during a time that is virtually zero .The replica was. The definition of instantaneous velocity is the speed of a moving item at a certain instant in time.
The rate of change of location during a relatively brief period of time is known as instantaneous velocity.
In the limit when the time (and thus the displacement) between the two places approaches zero, the instantaneous acceleration is the average acceleration between two points on the route.
so, both of them are perpendicular to each other.
To learn about instantaneous velocity
brainly.com/question/1222392
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It is a very reactive metal with 11 protons ,12 neutrons, 11 electrons, and 1 valence electron