Answer: B. 44.64 g
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
Mass of reactants = mass of iron + mass of oxygen = mass of iron + 34.7 g
Mass of product = mass of iron oxide = 79.34 g
As Mass of reactants = Mass of product
mass of iron + 34.7 g = 79.34 g
mass of iron = 44.64 g
Thus 44.64 g of iron was used in the reaction
Force applied causes
deformation in the object. It changes the relative positions of
constituent particles in the crystal lattice.
As soon as that happens, the interatomic or intermolecular forces come
into play and they, tend to restore the solid back to it's original
shape.
This restoring force per unit area is called Stress . When external forces are removed, the internal forces tend to restore the solid back.
This property is called Elasticity .
However, no material is perfectly elastic and what happens is that, the body is not able to restore itself completely.
Answer:
Velocity is 2.17 m/s at an angle of 9.03° above X-axis.
Explanation:
Mass of object 1 , m₁ = 300 g = 0.3 kg
Mass of object 2 , m₂ = 400 g = 0.4 kg
Initial velocity of object 1 , v₁ = 5.00i-3.20j m/s
Initial velocity of object 2 , v₂ = 3.00j m/s
Mass of composite = 0.7 kg
We need to find final velocity of composite.
Here momentum is conserved.
Initial momentum = Final momentum
Initial momentum = 0.3 x (5.00i-3.20j) + 0.4 x 3.00j = 1.5 i + 0.24 j kgm/s
Final momentum = 0.7 x v = 0.7v kgm/s
Comparing
1.5 i + 0.24 j = 0.7v
v = 2.14 i + 0.34 j
Magnitude of velocity

Direction,

Velocity is 2.17 m/s at an angle of 9.03° above X-axis.