The mass of the box would be 30!
Newton’s first law is commonly stated as:
An object at rest stays at rest and an object in motion stays in motion.
However, this is missing an important element related to forces. We could expand it by stating:
An object at rest stays at rest and an object in motion stays in motion at a constant speed and direction unless acted upon by an unbalanced force.
By the time Newton came along, the prevailing theory of motion—formulated by Aristotle—was nearly two thousand years old. It stated that if an object is moving, some sort of force is required to keep it moving. Unless that moving thing is being pushed or pulled, it will simply slow down or stop. Right?
This, of course, is not true. In the absence of any forces, no force is required to keep an object moving. An object (such as a ball) tossed in the earth’s atmosphere slows down because of air resistance (a force). An object’s velocity will only remain constant in the absence of any forces or if the forces that act on it cancel each other out, i.e. the net force adds up to zero. This is often referred to as equilibrium. The falling ball will reach a terminal velocity (that stays constant) once the force of air resistance equals the force of gravity.
Hope this help
Answer:
Wedge
Explanation:
Scissors are a pair of wedges that are combined together.
Answer
given,
initial speed of hockey player= 0 m/s
mass of the helmet, m = 1.3 Kg
initial speed of the helmet, u = 0 m/s
final speed of the helmet, v = 6 m/s
recoil speed of the hockey player, v' = 0.25 m/s
we need to calculate the mass of the hockey player, M = ?
using conservation of momentum
m u + M u' = M v' + m v
initial speed of ice skater is zero
1.3 x 0 + M x 0 = M x (-0.25) + 1.3 x 6
negative sign is taken because recoil velocity is in opposite direction
0 = -0.25 M + 7.8
0.25 M = 7.8
M = 31.2 Kg
Hence, the mass of the young hockey player is equal to 31.2 Kg
