Answer:
D. 4Al + 3O2 → 2Al2O3
Explanation:
Chemical reactions involves the chemical combination of two or more substances called REACTANTS to yield other substances called PRODUCTS. However, in accordance with the LAW OF CONSERVATION OF MASS, the amount of reactants must be equal to that of the products.
To accomplish this, the reaction must be BALANCED. A balanced equation is an equation in which the number of atoms of each element in the reactant side equals the number of atoms in the product side. In this reaction involving Aluminum and Oxygen to give Aluminum oxide as follows:
Al + 02 → Al2O3
A coefficient is used to balance the number of atoms on both sides of the equation as follows:
4Al + 3O2 → 2Al2O3
Answer:
u=36.8m/s
Explanation:
because of the acceleration is a constant acceleration we can use one of the "SUVAT" equations
u^2=v^2-2ā*s. where:
u^2 stands for intial velocity
v^2 stands for final velocity
since the cougar skidded to a complete stop the final velocity is zero.
u^2=v^2-2ā*s
u^2=(0)^2 -2(-2.87 m/s^2)*236 m
u^2=0+5.74m/s^2* 236m
u^2=1354.64m^2/s^2
u=√1354.64m^2/s^2
u=36.8m/s (approximate value)
when ever the acceleration is constant you can use one of the following equation to find the required value.
1. v = u + at. (no s)
2. s= 1/2(u+v)t. (no ā)
3. s=ut + 1/2at^2. ( no v)
4. v^2=u^2 + 2āS. (no t). 5. s= vt - 1/2at^2. (no u)
Its velocity would be constant
The 4 significant figures of 31,546,000 are all 8 of the digits.
Answer: The initial force is reduced a factor 1/4 when the separation between charge is doubled
Explanation: As it well known the electric force between two charges is given by:
Finitial=k*q1*q2/d^2 where d is the distance between charges and k is a constant
if the distance is doubled this means 2*dinitial thus the new force is equal to F initial* 1/4