Answer:
The final velocity of the object after 2 seconds is 30 m/s
Explanation:
Given;
constant downward acceleration, a = 10 m/s²
initial velocity of the object falling down, v = 10 m/s
time of fall, t = 2 s
The final velocity of the object is given by;
v = u + at
where;
v is the final velocity
v = 10 + (10)(2)
v = 10 + 20
v = 30 m/s
Therefore, the final velocity of the object after 2 seconds is 30 m/s
Speed= distance/ time so distance = speed * time= 28 * 20= 560m .. so the answer is 560m.. l hope it helped :)
Mechanical energy is the energy that is possessed by an object due to its motion or due to its position. It can either be kinetics or potential. In this problem you know it starting position so you can calculate it's potential energy (PE):
<span>PE=mass∗gravity∗height=0.3kg∗9.8m/s2∗1.8m=?
</span>The answer will typically be given in joules:
1J=kg∗m2s2 Could be wrong... But I believe it is 5.3...? as a final product.
It is customary to work in SI units.
Calculate the volume of the concrete.
V = 3.7*2.1*5.8 cm³ = 45.066 cm³ = 45.066 x 10 ⁻⁶ m³
The mass is 43.8 g = 43.8 x 10⁻³ kg
The density is mass/volume.
Density = (43.8 x 10⁻³ kg)/(45.066 x 10⁻⁶ m³) = 971.9 kg/m³
Answer: 971.9 kg/m³
