Answer:
3m/s
Explanation:
Time=5s
Distance =15m
Speed=distance/time
Putting the values
Speed=15m/5s
Speed=3m/s is the answer
Hope it will help you. :)
Answer:
Applying enough force in one direction to move the object, making kinetic energy.
Explanation:
Simpleness
Answer: a) 3.85 days
b) 10.54 days
Explanation:-
Expression for rate law for first order kinetics is given by:

where,
k = rate constant = ?
t = time taken for decomposition = 3 days
a = let initial amount of the reactant = 100 g
a - x = amount left after decay process = 
First we have to calculate the rate constant, we use the formula :
Now put all the given values in above equation, we get


a) Half-life of radon-222:


Thus half-life of radon-222 is 3.85 days.
b) Time taken for the sample to decay to 15% of its original amount:
where,
k = rate constant = 
t = time taken for decomposition = ?
a = let initial amount of the reactant = 100 g
a - x = amount left after decay process = 


Thus it will take 10.54 days for the sample to decay to 15% of its original amount.
<h2>
Resultant is 235.54 pounds at an angle 44.16° to X axis.</h2>
Explanation:
Forces are 100 pound and 150 pound and angles with x axis are 20°and 60°.
That is force 1 is 100 pound with x axis at 20°
F₁ = 100 cos 20 i + 100 sin 20 j
F₁ = 93.97 i + 34.20 j
That is force 2 is 150 pound with x axis at 60°
F₂ = 150 cos 60 i + 150 sin 60 j
F₂ = 75 i + 129.90 j
F₁ + F₂ = 93.97 i + 34.20 j + 75 i + 129.90 j
F₁ + F₂ = 168.97 i + 164.10 j

Resultant is 235.54 pounds at an angle 44.16° to X axis.
Given parameters:
Mass of the car = 1000kg
Unknown:
Height = ?
To find the heights for the different amount potential energy given, we need to understand what potential energy is.
Potential energy is the energy at rest due to the position of a body.
It is mathematically expressed as:
P.E = mgh
m is the mass
g is the acceleration due to gravity = 9.8m/s²
h is the height of the car
Now the unknown is h, height and we make it the subject of the expression to make for easy calculation.
h = 
<u>For 2.0 x 10³ J;</u>
h =
= 0.204m
<u>For 2.0 x 10⁵ J;</u>
h =
= 20.4m
<u>For 1.0kJ = 1 x 10³J; </u>
h =
= 0.102m