Answer:
16000
Explanation:
Mass(m)=2Kg (1kg= 1ooo g then 2 kg=2000 g)
Velocity(v)= 4 meter
Acceleration due to gravity (g)=10m/s
We know that,
P.E= 1/2 mv^2
or, 1/2 × 2ooo × 4^2
or, 1/2×2000 ×16
or, 2000×8
Therefore= 16000
Answer:
m = 3 kg
The mass m is 3 kg
Explanation:
From the equations of motion;
s = 0.5(u+v)t
Making t thr subject of formula;
t = 2s/(u+v)
t = time taken
s = distance travelled during deceleration = 62.5 m
u = initial speed = 25 m/s
v = final velocity = 0
Substituting the given values;
t = (2×62.5)/(25+0)
t = 5
Since, t = 5 the acceleration during this period is;
acceleration a = ∆v/t = (v-u)/t
a = (25)/5
a = 5 m/s^2
Force F = mass × acceleration
F = ma
Making m the subject of formula;
m = F/a
net force F = 15.0N
Substituting the values
m = 15/5
m = 3 kg
The mass m is 3 kg
The cart experiences a frictional force which is directly proportional to its weight. This means that there must be a force applied on the car to balance the forces on the car to produce a net force of 0.
This is in accordance to Newton's first law which states that an object at rest will remain at rest and an object in motion will remain in motion unless an external force acts on it. The force must be a resultant force.
Therefore, the force needed increases with the total weight of the cart as well as with the added mass in a linear manner.
Explanation:
option A is the correct answer, if the gravitational acceleration is taken 10m/s²(rounding of 9.8/ms²).
hope this helps you.
