Explanation:
First, we need to calculate the constant force, that is, the ratio between the applied force and the rubber stretch due to the application of the force:
Now, we can know how far will an 18N force stretch the rubber. From (1):
The work done by the external force on the rubber is equal to its elastic potential energy:
Answer:
D) 8.0 s.
Explanation:
(The following exercise is written in Spanish. Hence, explanations will be held in such language.)
La energía requerida para elevar el ascensor es el cambio en la energía potencial gravitacional, cuya magnitud es:
Ahora, la potencia media es el resultado anterior dividido por el tiempo. Se despeja el tiempo de la ecuación:
La opción más aproximada es D.
There are missing data in the text of the problem (found them on internet):
- speed of the car at the top of the hill:
- radius of the hill:
Solution:
(a) The car is moving by circular motion. There are two forces acting on the car: the weight of the car
(downwards) and the normal force N exerted by the road (upwards). The resultant of these two forces is equal to the centripetal force,
, so we can write:
(1)
By rearranging the equation and substituting the numbers, we find N:
(b) The problem is exactly identical to step (a), but this time we have to use the mass of the driver instead of the mass of the car. Therefore, we find:
(c) To find the car speed at which the normal force is zero, we can just require N=0 in eq.(1). and the equation becomes:
from which we find
Answer:
F = 4000 N
Explanation:
given,
mass of rocket (M)= 5000 Kg
10 Kg gas burns at speed (m)= 4000 m/s
time = 10 s
average force = ?
at the end the rocket is at rest
by conservation of momentum
M v + m v' = 0
5000 x v - 10 x 4000 = 0
5000 v = 40000
v = 8 m/s
speed of rocket = 8 m/s
now,
we know
change in momentum = F x Δ t
F = 4000 N
Hence, the average force applied to the rocket is equal to F = 4000 N
Answer: A student walks 50 meters east, 40 meters north, 35 meters east, and then 20 m south. Then the magnitude and direction of the student's total displacement will be 87.32 m along the direction of AD or in east-south direction.
Explanation: To find the correct answer, we need to know about the Displacement of a body in motion.
<h3>What is displacement of a body in motion?</h3>
- The displacement is the shortest distance between initial and final positions of a body.
- It's a vector quantity, and can positive, negative, or zero.
- The magnitude of displacement is less than or equal to the distance travelled.
<h3>How to solve the problem?</h3>
- At first, we can draw a diagram showing the motion of the body.
- From the diagram, the displacement of the body will be equal to the distance between point A and D.
- To solve this, we can use Pythagoras theorem.
Thus, from the above calculations, we can conclude that, the displacement of the body will be equal to 87.32 m along the direction of AD or in east-south direction.
Learn more about the Displacement here:
brainly.com/question/28020108
#SPJ4