Answer:
31 m/s
Explanation:
As both the monkey and the darts are subjected to constant gravitational acceleration g = 9.8 m/s2 and both start from rest (vertically speaking). Their vertical position will always be the same. For the dart to hit the monkey, its horizontal position must be the same as the monkey's, which is unchanged before reaching the ground. Therefore, the time it takes for the dart to travel across 70 m must be less than the time it takes for the monkey to drop 25m to the ground. We can find it out using the following equation of motion
For the dart to takes less that 2.26 s to travel 70m, its horizontal speed must at least be 70 / 2.26 = 31 m/s
Answer:
Magnets can create electricity and electricity can create a magnetic force.
Both electric charges and magnets do not have to touch an object in order to exert a force on it.
Electromagnets use electricity to create a magnetic force.
Explanation:
Metals in general, are good heat conductors
Answer:
F = 3116.49 N
Explanation:
given,
mass of the child = 15 kg
speed = 59 mi/hr
time taken to come to rest = 0.11 s
force on the boy = ?
1 mi/hr = 0.447 m/s
59 mi/hr = 59 × 0.447 = 26.37 m/s
a=239.73 m/s²
the calculation of force
Force = mass × acceleration
F = m × a
F = 13 × 239.73
F = 3116.49 N