Answer:
No
Explanation:
The force of tension exerted by the string on the rock acts as centripetal force, so its direction is always towards the centre of the circle.
However, the direction of motion of the rock is always tangential to the circle: this means that the force is always perpendicular to the direction of motion of the rock.
As we know, the work done by a force on an object is

where
F is the magnitude of the force
d is the displacement of the object
is the angle between the force and the displacement
In this situation, F and d are perpendicular, so
, therefore
and the work done is zero:

The answer is <span>It protects the seed until it matures.
Through the process of elimination:
- </span><span>It protects the seed until it matures. YES. A female pine cone the unfertilized seeds until they become mature. Then, the cone opens and seeds fall out of the cone.
</span><span>- It makes food for the adult plant. NO. The food of plants in made of green leaves that contain chlorophyll in the process of photosynthesis.
- It allows for photosynthesis to occur. NO. The cones have nothing to do with photosynthesis but they are responsible for reproduction.
- It acts as an object to attract birds. NO. The birds look for colourful flowers while cones are woody.
- It serves as an ornamental object on the tree. NO. Every part of plants has more important function than serving as an ornamental object.</span><span>
</span>
Answer:
The amount of work the factory worker must to stop the rolling ramp is 294 joules
Explanation:
The object rolling down the frictionless ramp has the following parameters;
The mass of the object = 10 kg
The height from which the object is rolled = 3 meters
The work done by the factory worker to stop the rolling ramp = The initial potential energy, P.E., of the ramp
Where;
The potential energy P.E. = m × g × h
m = The mass of the ramp = 10 kg
g = The acceleration due to gravity = 9.8 m/s²
h = The height from which the object rolls down = 3 m
Therefore, we have;
P.E. = 10 kg × 9.8 m/s² × 3 m = 294 Joules
The work done by the factory worker to stop the rolling ramp = P.E. = 294 joules
Refer to the figure shown below.
Let m₁ and m₂ e the two masses.
Let a = the acceleration.
Let T = tension over the frictionless pulley.
Write the equations of motion.
m₂g - T = m₂a (1)
T - m₁g = m₁a (2)
Add equations (1) and (2).
m₂g - T + T - m₁g = (m₁ + m₂)a
(m₂ - m₁)g = (m₁ + m₂)a
Divide through by m₁.
(m₂/m₁ - 1)g = (1 + m₂/m₁)a
Define r = m₂/m₁ as the ratio of the two masses. Then
(r - 1)g = (1 +r)a
r(g-a) = a + g
r = (g - a)/(g + a)
With = 2 ft/s from rest, the acceleration is
a = 2/32.2 = 0.062 ft/s²
Therefore
r = (32.2 - 0.062)/(32.2 + 0.062) = 0.9962
Answer:
The ratio of masses is 0.9962 (heavier mass divided by the lighter mass).
Answer:c
Explanation:
Given
Alice launches with horizontal velocity 
Tom simply drops straight down from the edge
Time taken by both the person is same as they have same initial vertical velocity i.e. zero so the time taken to reach the ground is zero.
Although Alice will travel more horizontal distance compared to Tom.
Thus option c is correct