Answer:

Explanation:
The two cars are under an uniform linear motion. So, the distance traveled by them is given by:

is the same for both cars when the second one catches up with the first. If we take as reference point the initial position of the second car, we have:

We have
. Thus, solving for t:

Answer:
See below explanation
Explanation:
The correspondent chemical reaction for copper carbonate decomposed by heat is:
CuCO₃ (s) → CuO (s) + CO₂ (g)
Considering all molar mass (MM) for each element ( we consider rounded numbers) :
MM CuCO₃ = 123 g/mol
MM CuO = 79 g/mol
MM CO₂ = 44 g/mol
Statement mentions that scientis heated 123.6 g of CuCO₃ (almost a MM), until a black residue is obtained, which weights 79.6 g : this solid residue is formed by CuO, and the remaining mass (approximatelly 44 g) belongs to teh second product, this is, CO₂; as it is a gas compund, it is not certainly included on the solid residue.
So, law of conservation mass is true for this case, since: 123.6 g = 79.6 g + 44 g. As explained, on the solid residue, we don not include the 44 g, which "escaped" from our system, since it is a gas compound (CO₂)
Answer:


Explanation:
<u>Given Data:</u>
Weight = W = 65 N
Height = h = 2 m
Time = t = 4 secs
<u>Required:</u>
Power = P = ?
Work Done in the form of Potential Energy = P.E. = ?
<u>Formula:</u>
P.E. = Wh
P = P.E. / t
<u>Solution:</u>
P.E. = (65)(2)
P.E = 130 Joules
P = P.E. / t
P = 130 / 4
P = 32.5 Watts
![\rule[225]{225}{2}](https://tex.z-dn.net/?f=%5Crule%5B225%5D%7B225%7D%7B2%7D)
Hope this helped!
<h3>~AH1807 </h3>
Answer:
The velocity is 
Henrietta is at distance
from the under the window
Explanation:
From the question we are told that
The speed of Henrietta is 
The height of the window from the ground is 
Generally the time taken for the lunch to reach the ground assuming it fell directly under the window is

=>
=>
Generally the time taken for the lunch to reach Henrietta is mathematically represented as

Here
is the time duration that elapsed after Henrietta has passed below the window the value is given as 4 s
Now
=>
Generally the distance covered by Henrietta before catching her lunch is

=> 
=> 
Generally the speed with which Bruce threw her lunch is mathematically represented as


Answer:
Power factor = 0.87 (Approx)
Explanation:
Given:
Load = 1 Kw = 1000 watt
Current (I) = 5 A
Supply (V) = 230 V
Find:
Power factor.
Computation:
Power factor = watts / (V)(I)
Power factor = 1,000 / (230)(5)
Power factor = 1,000 / (1,150)
Power factor = 0.8695
Power factor = 0.87 (Approx)