Let's use Newton's 2nd law of motion:
Force = (mass) x (acceleration)
Force = (68 kg) x (1.2 m/s²) = 81.6 newtons .
Answer:
<em>0.25</em>
Explanation:
According to newtons law of motion
\sum F_x = ma
F_f = ma
nR = ma
nmg = ma
ng = a
n = a/g
g is the acceleration due to gravity
Given
a = 2.42m/s²
g = 9.8m/s²
Substitute into the formula;
n = 2.42/9.8
n = 0.25
<em>Hence the coefficient of kinetic friction is 0.25</em>
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Answer:
a)
Explanation:
- A block sliding down an inclined plane, is subject to two external forces along the slide.
- One is the component of gravity (the weight) parallel to the incline.
- If the inclined plane makes an angle θ with the horizontal, this component (projection of the downward gravity along the incline, can be written as follows:

(taking as positive the direction of the movement of the block)
- The other force, is the friction force, that adopts any value needed to meet the Newton's 2nd Law.
- When θ is so large, than the block moves downward along the incline, the friction force can be expressed as follows:
- The normal force, adopts the value needed to prevent any vertical movement through the surface of the incline:
- In equilibrium, both forces, as defined in (1), (2) and (3) must be equal in magnitude, as follows:

- As the block is moving, if the net force is 0, according to Newton's 2nd Law, the block must be moving at constant speed.
- In this condition, the friction coefficient is the kinetic one (μk), which can be calculated as follows:

Answer: I think maybe thru Convection?
Explanation:
cause convection causes the heat to stay to the top and the cold air stay's to the bottom so maybe i would say Convection.... Is there any answer choices?
Answer:
Angular acceleration, is 
Explanation:
Given that,
Initial speed of the drill, 
After 4.28 s of constant angular acceleration it turns at a rate of 28940 rev/min, final angular speed, 
We need to find the drill’s angular acceleration. It is given by the rate of change of angular velocity.

So, the drill's angular acceleration is
.