Answer:
ΔL = L0 C ΔT
We need to find C the constant of expansivity
C = ΔL / (L0 ΔT)
C = .96 / (15.04 * 65) = 9.82 * 10^-4 / deg C
 
        
             
        
        
        
Answer:
H = 45 m
Explanation:
First we find the launch velocity of the ball by using the following formula:
v₀ = √(v₀ₓ² + v₀y²)
where,
v₀ = launching velocity = ?
v₀ₓ = Horizontal Component of Launch Velocity = 15 m/s
v₀y = Vertical Component of Launch Velocity = 30 m/s
Therefore,
v₀ = √[(15 m/s)² + (30 m/s)²]
v₀ = 33.54 m/s
Now, we find the launch angle of the ball by using the following formula:
θ = tan⁻¹ (v₀y/v₀ₓ)
θ = tan⁻¹ (30/15)
θ = tan⁻¹ (2)
θ = 63.43°
Now, the maximum height attained by the ball is given by the formula:
H = (v₀² Sin² θ)/2g
H = (33.54 m/s)² (Sin² 63.43°)/2(10 m/s²)
<u>H = 45 m</u>
 
        
             
        
        
        
Answer:
2.62seconds
Explanation:
Speed is defined as the ratio of the distance covered by a body with respect to time. 
Speed v = Distance (s)/Time (t)
For a traveling sound wave, the distance between the source of a sound and the reflector is '2S'.
Speed v = 2 × distance (S)/Time (T)
V = 2S/t
2S = vt
Given speed of the wave = 342m/s
Distance covered = 450m
t = 2S/v
t = (2×450)/343
t = 900/343
t = 2.62seconds
It will take him 2.62seconds for him to hear his own voice echo off of the wall.
 
        
                    
             
        
        
        
The first law of thermodynamics states the conservation of energy and heat where the total energy in an isolated system may be transformed into another, but never created or destroyed. If 286 J of energy was released to the room, then also 286 J of energy was also removed from food in that refrigerator assuming it is an isolated system.   :)
 Read more on Brainly - 
brainly.com/sf/question/3844753I tried to help