Answer:
Explanation:
Given the height reached by a balloon after t sec modeled by the equation
h=1/2t²+1/2t
a) To calculate the height of the balloon after 40 secs we will substitute t = 40 into the modeled equation and calculate the value of t
If h(t)=1/2t²+1/2t
h(40) = 1/2(40)²+1/2 (40)
h(40) = 1600/2 + 40/2
h(40) = 800 + 20
h(40) = 820 feet
The height of the balloon after 40 secs is 820 feet
b) Velocity is the change of displacement of a body with respect to time.
v = dh/dt
v(t) = 2(1/2)t²⁻¹ + 1/2
v(t) = t + 1/2
when v = 0sec
v(0) = 0 + 1/2
v(0) = 1/2 ft/sec
at v = 30secs
v(30) = 30 + 1/2
v(30) = 30 1/2 ft/sec
average velocity = v(30) - v(0)
average velocity = 30 1/2 - 1/2
average velocity of the balloon between t = 0 and t = 30 = 30 ft/sec
c) Velocity is the change of displacement of a body with respect to time.
v = dh/dt
v(t) = 2(1/2)t²⁻¹ + 1/2
v(t) = t + 1/2
The velocity of the balloon after 30secs will be;
v(30) = 30+1/2
v(30) = 30.5ft/sec
The velocity of the balloon after 30 secs is 30.5 feet/sec
Answer:
c) curves downward, below the initial velocity vector
Explanation:
A projectile is usually launched from a height, where it is launched with an initial velocity. From that point the gravitational force begins to act on the projectile causing it to decay. As time passes, the projectile advances but its height decreases. So its trajectory is curved downward, below the initial velocity vector.
Answer:
<u>FALSE.</u>
Explanation:
Newton's third law states that :
- <em>Every action has equal and opposite reaction</em>
- <em>That is , the magnitude is the same but the directions are opposite</em>
- <em>The action reaction forces DONOT operate on the same body.</em>
For example ,
If a block is kept on the ground , the action force is the normal force acting on it due to the ground. <em>BUT , NOTE THAT : the reaction force isn't the gravitational force on the body ! It is the normal force acting on the ground due to the block !</em>
Thus,
we conclude that action and reaction forces donot act on the same body and therefore , this case has the <u>answer : FALSE </u>
Operant conditioning, sometimes called <em>instrumental learning</em>, was first extensively studied by Edward L. Thorndike, who observed the behavior of cats trying to escape from home-made puzzle boxes.
Hope this helps!
Answer:
Explanation:
a) ωp = 2π radians / 1.7 s = <u>3.7 rad/s</u>
b) ωs = 3.7 rad/s(9.5 cm / 4.5 cm) = 7.8 rad/s
v = (ωs)R = 7.8(65) = 507 cm/s or <u>5.1 m/s</u>
c) ωs = 3.5 m/s / 0.65 m = 5.38 rad/s
ωp = 5.38(4.5 cm / 9.5 cm) = 2.55 rad/s
t = θ/ω = 2π / 2.55 = 2.463... <u>2.5 s</u>
