Answer:
H = start height (v = 0)
h = present height
v = present speed
assuming no friction
total energy = PE + KE
mgH = mgh + .5mv^2
if PE = KE then
mgH = mgh + mgh
h = H/2
potential energy = kinetic energy when object is at half its start height.
Explanation:
Answer:
<u>0.04 °C⁻¹</u>
Explanation:
First, we need to calculate linear expansivity, then after finding that value, we can move on to finding the area expansivity.
<u />
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Finding Linear Expansivity :
⇒ α = Final length - Original length / (Original length × ΔT)
⇒ α = 9 - 4 / (4 × 70 - 20)
⇒ α = 5 / 5 × 50
⇒ α = <u>0.02</u>
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Finding Area Expansivity :
⇒ Area Expansivity = 2 × Linear Expansivity
⇒ β = 2 × α
⇒ β = 2 × 0.02
⇒ β = <u>0.04 °C⁻¹</u>
In Physics, 'work' has a very clear definition:
It's (strength of a force) times (distance through which the force acts).
'Work' has the units of Energy.
If you push against a shopping cart with 30 newtons of force, and
you keep pushing while the cart moves 4 meters, then you have
done (30 x 4) = 120 newton-meters of work = 120 "Joules".
Explanation:
Given parameters:
Distance = 15miles north = 24140.2m
Initial velocity = 0m/s
Final velocity = 4m/s
Unknown:
Speed, velocity and acceleration = ?
Solution:
The speed is the distance divide by time. It is a scalar quantity and has no directional attribute.
Speed = 
The speed of the student is 4m/s
Velocity is the displacement divided by time. It is a vector quantity which specifies the direction and magnitude;
Velocity = 
The velocity of the student is 4m/s due north
Acceleration is the change in velocity with time;
To find the acceleration, we use
v² = u² + 2as
v is the final velocity
u is the initial velocity
a is the acceleration
s is the distance
4² = 0² + 2x a x 24140.2
a = 
= 0.00033m/s²
