The answer is speed: 4.7 km/h, velocity: 3.3 km/h.
Distances and time are given:
d1 = 4 km
d2 = 3 km
d3 = 5 km
t = 1.5 h
The speed can be expressed as a distance (d) divided by time (t). The average speed (s) is total distance travelled divided by time:
s = (d1 + d2)/t = (4+3)/1.5 = 7/1.5 = 4.7 km/h
The average velocity (v) is total displacement (d₁) from the starting point divided by time. Since Mary's starting point was home, and she walked to the supermarket, which is 5.0 kilometers from her own home, her displacement is 5 km:
v = d₁/t = 5/1.5 = 3.3 km/h
Answer:
a. Both wires have the same resistivity
Explanation:
For the resistance of a wire , following formula holds good .
R = ρ l / S , R is resistance , l is length , S is cross sectional area and ρ is resistivity of the material that the wire is made of. Resistance is dependent on length and cross sectional area but resistivity does not depend upon length or cross sectional area . It only depends upon the type of material.
If we replace copper wire with aluminium wire , then resistivity will change .
Hence , since the wire remains made of copper , resistivity will not change.
Newton’s Law: F = MA
A = F/M (change equation)
12.6 N/ 2.4 kg = 5.25
Answer: acceleration is 5.25 m/s^2
C, electrons. Ion<span> of an </span>element has<span> the </span>same<span> nucleus, the </span>same number<span> of protons and neutrons, with a </span>different number<span> of electrons.</span>
<span>Cells undergo mitosis for three main reasons:
-To repair and/or replace old or damaged cells.
-During periods of cell and tissue growth
-When the body needs exact replicas/copies of cells e.g. hair cells and blood cells.</span>
