a. work is the time it takes to move an object once acted upon by a force
Answer:
P = 75 W
Explanation:
given,
Distance, L = 8 m
Force,F = 150 N
Time, t = 16 s
Work by the climber
Work done = Force x displacement
W = F. L
W = 150 x 8
W = 1200 J
We know,
P = 75 W
Hence, Power climber is using to climb is equal to 75 W.
The metal ball lost energy while the putty ball gained energy.
<h3>What is momentum?</h3>
Momentum is the product of mass and velocity of the body. We must note that momentum before collision is equal to momentum after collision.
1) Kinetic energy before collision = 1/2mv^2 = 0.5 * 6 * 4 = 12 J
2) kinetic energy after collision = 0.5 * 6 * 2= 6 J
3) Kinetic energy of putty ball = 0.5 * 6 * 2= 6 J
4) Energy lost by the metal ball = 12 J - 6 J = 6 J
5) Energy gained by the putty ball = 6 J - 0J = 6 J
6) The rest of the energy was converted to heat after the collision.
Learn more about kinetic energy: brainly.com/question/999862
By Newton's second law, the net vertical force acting on the object is 0, so that
<em>n</em> - <em>w</em> = 0
where <em>n</em> = magnitude of the normal force of the surface pushing up on the object, and <em>w</em> = weight of the object. Hence <em>n</em> = <em>w</em> = <em>mg</em> = 196 N, where <em>m</em> = 20 kg and <em>g</em> = 9.80 m/s².
The force of static friction exerts up to 80 N on the object, since that's the minimum required force needed to get it moving, which means the coefficient of <u>static</u> friction <em>µ</em> is such that
80 N = <em>µ</em> (196 N) → <em>µ</em> = (80 N)/(196 N) ≈ 0.408
Moving at constant speed, there is a kinetic friction force of 40 N opposing the object's motion, so that the coefficient of <u>kinetic</u> friction <em>ν</em> is
40 N = <em>ν</em> (196 N) → <em>ν</em> = (40 N)/(196 N) ≈ 0.204
And so the closest answer is C.
(Note: <em>µ</em> and <em>ν</em> are the Greek letters mu and nu)
<u>ALL of the following work assumes NO AIR RESISTANCE:</u>
1). an object moving under the influence of only gravity, and not in orbit; its horizontal velocity is constant, and its vertical motion is accelerated downward at 9.8 m/s²
2). a parabola
3). Horizontal: velocity is constant, acceleration is zero. . . . Vertical: acceleration is 9.8 m/s² downward, velocity depends on whether it was launched, thrown up, thrown down, dropped, etc.
4). a). the one that was thrown horizontally; b). both hit the ground at the same time; c). both hit the ground with the same vertical velocity
5). a). zero; b). zero; c). gravity ... 9.8 m/s² down; d). 3.06 seconds; e). 4.38 m/s; f). 30 m/s g). no; gravity has no effect on horizontal motion
6). a). 1.8 seconds; b). 13.1 meters; c). 17.6 m/s down; d). 7.3 m/s; gravity has no effect on horizontal motion
7). 45 m/s
8). without air resistance, the ball is traveling horizontally at 13 km/hr, and it lands back in your hand
9). a). 4.49 m/s; b). 29.7 m/s
10). 7.24 meters
11). 700 meters
12). A). 103.7 meters ( ! she's in big trouble ! ); B). 17.5 meters
