Answer:
1st one
identity of the H₂O
When water (H2O) freezes into ice, some of the properties have changed but the identity of the H2O is the same. Explanation; Water can exist in liquid, solid; ice and gaseous state; steam. Freezing occurs when water is continuously cool until it turns to solid ice, water freezes at zero degree Celsius
Hope This Helps
Answer:
Change in KE is 40 J
Explanation:
Recall that the impulse exerted on an object equal the change of momentum of the object (ΔP), which in time is defined as the product of the force exerted on it times the time the force was acting:
Change in momentum is: ΔP = F * Δt
In our case,
ΔP = 40 N * 1 sec = 40 N s
Since the object was initially at rest, its initial momentum was zero, and the final momentum should then be 40 N s.
So, the initial KE was 0, and the final (KEf) can be calculated using:
KEf = 1 /(2 m) Pf^2 = 1 / (40) 40^2 = 40 J
So, the change in kinetic energy is:
KEf - KEi = 40 J - 0 j = 40 J
Answer:
0.26
Explanation:
Given that :
Diameter of ball = 3.81 cm = 3.81/100 = 0.0381 m
Radius (r) = 0.0381 / 2 = 0.01905 m
Average density of ball (Db) = 0.0842 g/cm³ = (0.0842 / 1000)kg / 10^-6 = 0.0842/ 1000 * 10^6 = 84.2kg/m³
Density of water (Dw) = 1000kg/m³
Volume of hollow ball: (4/3) * pi * r³
V = (4/3) * π * 0.01905^3
V = 0.0000289583 m³
Required force = (Dw * V * g) - (Db * V * g)
= (1000 * 0.0000289583 * 9.8) - (84.2 * 0.0000289583 * 9.8)
= 0.259896109172
= 0.2598 N
