Answer:
a) correct answer is C
, b) 14º from the west to the north, c) v_{1g} = 300.79 km / h
Explanation:
This is a relative speed exercise using the addition of speeds.
1) when it is not specified regarding what is being measured, the medicine is carried out with respect to the Z Earth, therefore the correct answer is C
2 and 3) In this case we must compose the speed using the Pythagorean Theorem.
² = 
² + 
²
where v_{1a} is the speed of the airplane with respect to the air, v_{1g} airplane speed with respect to the Earth, v_{ag} air speed with respect to the Earth
in this case let's clear the speed of the airplane with respect to the Earth
v_{1g} = √(v_{1a}² - v_{ag}²)
v_{1g} = √ (310² - 75²)
v_{1g} = 300.79 km / h
we find the direction of the airplane using trigonometry
sin θ = v_{ag} / v_{1a}
θ = sin⁻¹ (v_{ag} /v_{1a})
θ = sin⁻¹ (75/310)
θ= 14º
the pilot must direct the aircraft at an angle of 14º from the west to the north
Explanation:
a = (Vf-Vi)/t
= (10m/s - 15m/s)/2s
a = -5 / 2 m/s^2
• so the dog diaccelerate at the rate of 5/2 m/s^2
hope it helps
Answer:
Work done.
Explanation:
The skater who lifts has to overcome the partner's weight. When lifted up by 1 meter, her potential energy increases by (mass)x(gravitational acceleration)x(1meter), which is the amount of work done.
(This all assumes lifting vertically and no other forces being part of the picture)
Answer:
the net force is the same direction as the acceleration
Explanation:
so toward the center of the circle about which the object is constantly moving.
Answer:
H = 3.9 m
Explanation:
mass (m) = 48 kg
initial velocity (initial speed) (U) = 8.9 m/s
final velocity (V) = 1.6 m/s
acceleration due to gravity (g) = 9.8 m/s^{2}
find the height she raised her self to as she crosses the bar (H)
from energy conservation, the change in kinetic energy = change in potential energy
0.5m(V^{2} - [test]U^{2}[/tex]) = mg(H-h)
where h = initial height = 0 since she was on the ground
the equation becomes
0.5m(V^{2} - [test]U^{2}[/tex]) = mgH
0.5 x 48 x (1.6^{2} - [test]8.9^{2}[/tex]) = 48 x 9.8 x H
-1839.6 = 470.4 H (the negative sign indicates a decrease in kinetic energy so we would not be making use of it further)
H = 3.9 m
