the answer is (A) the movement of the magnet relative to the coil
( (77/4) + 76/2 )/2 = 28.625 km/h is what i got
Answer:
Surely Achilles will catch the Tortoise, in 400 seconds
Explanation:
The problem itself reduces the interval of time many times, almost reaching zero. However, if we assume the interval constant, then it is clear that in two hours Achilles already has surpassed the Tortoise (20 miles while the Tortoise only 3).
To calculate the time, we use kinematic expression for constant speed:

The moment that Achilles catch the tortoise is found by setting the same final position for both (and same time as well, since both start at the same time):

Answer:
Work done = 35467.278 J
Explanation:
Given:
Height of the cone = 4m
radius (r) of the cone = 1.2m
Density of the cone = 600kg/m³
Acceleration due to gravity, g = 9.8 m/s²
Now,
The total mass of the cone (m) = Density of the cone × volume of the cone
Volume of the cone = 
thus,
volume of the cone =
= 6.03 m³
therefore, the mass of the cone = 600 Kg/m³ × 6.03 m³ = 3619.11 kg
The center of mass for the cone lies at the
times the total height
thus,
center of mass lies at, h' = 
Now, the work gone (W) against gravity is given as:
W = mgh'
W = 3619.11kg × 9.8 m/s² × 1 = 35467.278 J
Answer: It's hard to say without characterizing the collision. But it will be either A if the collision is totally in-elastic, or B if the collision is totally elastic. It could be anywhere in between for partially elastic collisions.
Explanation:
momentum is conserved, so initial system momentum will be left to right.
The velocity of the center of mass is 50(5) / 550 = 0.4545... m/s
In an elastic collision, the lead ball will move off at twice that speed or 0.91 m/s to the right.
The steel ball will bounce back and move away at 0.91 - 5 = -4.1 m/s . The negative sign indicates the steel ball has reversed course and has negative momentum
In a totally in-elastic collision, both balls would move to the right at 0.45 m/s. The steel ball will still have positive momentum.