Answer:
vf = 12.51 m/s
Explanation:
Newton's second law to the grocery cart:
∑F = m*a Formula (1)
∑F : algebraic sum of the forces in Newton (N)
m : mass s (kg)
a : acceleration (m/s²)
We define the x-axis in the direction parallel to the movement of the grocery cart and the y-axis in the direction perpendicular to it.
Forces acting on the grocery cart
W: Weight of the block : In vertical direction downward
N : Normal force : In vertical direction upward
F : horizontal force
Calculated of the mas of the grocery cart (m)
W = m*g
m = W/g
W = 94.0 N , g = 9.81 m/s²
m = 94/9.81
m = 9.58 Kg
Calculated of the acceleration of the grocery cart (a)
∑F = m*a
F = m*a
42.6 = (9.58)*a
a = (42.6) / (9.58)
a = 4.45 m/s²
Kinematics Equation of the grocery cart
Because the grocery cart moves with uniformly accelerated movement we apply the following formula to calculate its final speed :
vf²=v₀²+2*a*d Formula (2)
Where:
d:displacement (m)
v₀: initial speed (m/s)
vf: final speed (m/s)
a: acceleration (m/s²)
Data:
v₀ = 0
a = 4.45 m/s²
d = 17.6 m
We replace data in the formula (2) :
vf²=v₀²+2*a*d
vf² = 0+2*(4.45)*(17.6)
vf² = 156.64
vf = 12.51 m/s
Answer:
B
Explanation:
<em>A. His speed is 0 m/s
</em>
<em>B. His velocity is 12 m/s
</em>
<em>C. His velocity is 0 m/s
</em>
<em>D. His acceleration is 12 m/s</em>
Total distance traveled by John = 120 + 120 = 240 meters
Total time taken by John to cover the distance = 10 + 10 = 20 s
<em>Average speed of John = total distance traveled/total time taken</em>
= 240/20 = 12 m/s
Hence, the average speed/velocity of John throughout the journey is 12 m/s.
The correct option is B.
The formulas used to analyze the horizontal and vertical motion of projectiles launched at an angle involve the use of tangent, cosine and sine.
<h3>
What is vertical motion of a projecile?</h3>
The vertical motion of a projectile is affected by gravity and the velocity of vertical motion given by the following formula;
Vy = Vsinθ
<h3>
What is horizontal motion of a projecile?</h3>
The horizontal velocity of a projectile is given by the following formula;
Vx = Vcosθ
<h3>Direction of the motion</h3>
The direction of the motion is calculated as follows;
tanθ = Vy/Vx
Thus, the formulas used to analyze the horizontal and vertical motion of projectiles launched at an angle involve the use of tangent, cosine and sine.
Learn more about vertical motion here: brainly.com/question/24216590
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Well, actually a heat engine using the Carnot cycle whose cold reservoir is maintained at 0 K could in principle be 100% efficient, even if the hot reservoir was merely at the ambient temperature. Since it costs no energy at all to maintain a heat reservoir at the ambient temperature as long as you have a perfect thermal connection to a large thermal capacitor like your swimming pool or a nearby aquifer you’d have built a perpetual motion machine.
Every living thing would die
