Answer:
3.5m/s^2
Explanation:
From Newton's second Law of Motion
F = ma
Where F is the applied force, m is the mass of the object and a is the acceleration.
F = 350 N
Mass = 100kg
350N = 100×a
a = 350/100
a = 3.5m/s^2
The acceleration of the object will be 3.5m/s^2
Answer:
T = 5.36 s
Explanation:
given,
depth of the mine shaft = 122.5 m
speed of the sound = 340 m/s
time taken = ?
time taken by the stone to reach at the bottom
using equation of motion

initial speed , u = 0 m/s


t = 5 s
time taken by the sound to travel
d =v x t


t = 0.36 s
total time taken for the sound to reach carol after dropping the stone
T = 5 + 0.36
T = 5.36 s
Work = force * distance.
We must produce twice as much energy as we are lifting the weight twice as high.
But we are not increasing the force so we must increase the length of the ramp ( distance ) instead.
The new length will be twice as great as the previous length.
So 8 metres is required.
25 kg * 8 m = work = 100 kg * 2 m
Answer:
a. negative
b. zero
Explanation:
work is the change in the energy of a system due to external forces
work is done when a force moves a load through a distance in the direction of the force
The work done by a force on a system is positive when the force and the force displacement point in the same direction and negative when they point in opposite directions
in the scenario we are considering in the question, the force (the hand) moves the block vertically upwards but the displacement of the block reduces (in the opposite direction) since it decelerates. as such the work done by gravity on the block is negative.
the work done on the block is zero if the system consists of the block and the earth because there is no gravitational force exerted on the system