Answer:
Explanation:
F = ma
m = F/a
m = 107.2/1.6 = 67 kg
so Naoki's mass must be the total mass - mass of the bike
so her mass is 67 - 9 = 58 kg...B
Answer:
Kinetic energy of bigger rock will be more than that of smaller one.
Explanation:
Kinetic energy of the rock is given by,
Kinetic energy = 
As velocity of both the rocks are same. Thus, kinetic energy is directly proportional to the mass of the rock
Kinetic energy ∝ mass
So, For greater mass kinetic energy will be greater and for smaller mass kinetic energy will be smaller.
Hence, Kinetic energy of bigger rock will be more than that of smaller one.
Answer:
60 kg m/s
Explanation:
Let
be the acceleration of the object.
As the acceleration of the object is constant, so

Given that applied force, F=6.00 N,
From Newton's second law, we have
,
[from equation (i)]


[given that time, t=10 s and F=6 N]

Here mv is the final momentum of the object and mu is the initial momentum of the object.
So, the change in the momentum of the object is mv-mu.
Hence, the change in the momentum of the object is 60 kg m/s.
Answer:
17.1
Explanation:
The distance ahead, of the deer when it is sighted by the park ranger, d = 20 m
The initial speed with which the ranger was driving, u = 11.4 m/s
The acceleration rate with which the ranger slows down, a = (-)3.80 m/s² (For a vehicle slowing down, the acceleration is negative)
The distance required for the ranger to come to rest, s = Required
The kinematic equation of motion that can be used to find the distance the ranger's vehicle travels before coming to rest (the distance 's'), is given as follows;
v² = u² + 2·a·s
∴ s = (v² - u²)/(2·a)
Where;
v = The final velocity = 0 m/s (the vehicle comes to rest (stops))
Plugging in the values for 'v', 'u', and 'a', gives;
s = (0² - 11.4²)/(2 × -3.8) = 17.1
The distance the required for the ranger's vehicle to com to rest, s = 17.1 (meters).
To protect a material from the influence of an external magnetic field, the material should be kept in soft iron ring.
So the correct answer is A.
Hope this helps,
Davinia.