Answer:
average speed
= [(10-3)/12 km] / [(49.5-32.0)/60 hour]
= 5*7 / 17.5
= 2 km/h .
Answer:
W and X
Explanation:
When escaping a rip current, one should always walk to the side until you escape from the rip current. If you walk towards the shore, you have the ability to keep getting dragged toward the current, such as with X and Y.
Answer:
T = 23.92 m
Explanation:
given,
mass of the diver = 50.9 Kg
Resistant force from the water = f = 1492 N
diver come top rest under water at a distance = 6 m
acceleration due to gravity = 9.81 m/s²
final velocity = v = 0 m/s
initial velocity = u = ?
total distance = ?
Now acceleration of body under water
f = m a
using equation of motion
v² = u² + 2 a s
0 = u² - 2 x 29.31 x 6
u = 18.75 m/s
now.
calculating distance of the diver in air
v² = u² + 2 a s
0 = 18.75² - 2 x 9.81 x s
s = 17.92 m
total distance
T = 17.92 + 6
T = 23.92 m
the total distance between the diving board and the diver’s stopping point underwater T = 23.92 m
Answer: a) 1.846m
b) 0.923m
Explanation: given that height h = 1.9m
Assume his eyes are 5.4 cm below the top of his head
5.4 cm = 5.4 / 100 = 0.054 m
1.9 – 0.054 = 1.846 meter
The top of the mirror should be placed at 1.846m
That is the vertical distance from his eyes to top of his head.
Light must travel from the top of his head to the mirror in order for him to see the head. Then travel from this position to his eyes. To do this, the mirror must be placed at a position that is halfway between his eyes and the top of his head.
The minimal vertical distance from the level of the person’s eyes to the top of the mirror will be:
d = ½ ×1.846 = 0.923 meters
