Answer:
51.2 J, 86.2 J, 137.4 J
Explanation:
The kinetic energy of the ball is given by:
where
m = 0.40 kg is its mass
v = 16 m/s is its speed
Substituting,
The potential energy of the ball is given by
where
m = 0.40 kg
is the acceleration of gravity
h = 22 m is the heigth of the cliff
Substituting,
Finally, the total mechanical energy is the sum of the kinetic energy and the potential energy:
Answer:
150.8 J
Explanation:
The heat released by the copper wire is given by:
where:
m = 10.0 g is the mass of the wire
Cs = 0.377 j/(g.C) is the specific heat capacity of copper
is the change in temperature of the wire
Substituting into the equation, we find
And the sign is negative because the heat is released by the wire.
Explanation:
Acceleration is the change in speed over change in time.
a = Δv / Δt
a. The car's acceleration is:
a = (80 km/h − 0 km/h) / 10 s
a = 8 km/h/s
So every second, the speed increases by 8 km/h.
b. The cyclist's acceleration is:
a = (16 m/s − 4.0 m/s) / 5.6 s
a = 2.1 m/s²
c. The stone's speed is:
10.0 m/s² = (v − 0 m/s) / 3.5 s
v = 35 m/s
d. The time is:
1.6 m/s² = (10 m/s − 0 m/s) / t
t = 6.3 s
Answer:
210
Explanation:
A ball rolls horizontally off the cliff at a speed of 30 m/s. It takes 7 seconds for the ball to hit the ground. What is the height of the cliff and the horizontal distance traveled by the ball?
S = (1/2)*9.8 m/s^2 * 7^2 = 240.1 m if the ball is very dense so air resistance, and therefore terminal velocity, can be ignored.
S = v * t = 30 m/s * 7 s = 210 m for the horizontal distance, again assuming negligible air resistance.
<u>Answer:</u>
The height of ramp = 124.694 m
<u>Explanation:</u>
Using second equation of motion,
From the question,
u = 31 m/s; s = 156.3 m, a=0
substituting values
t =
= 5.042 s
Similary, for the case of landing
t = 5.042 s; initial velocity, u =0
acceleration = acceleration due to gravity, g = 9.81
Substituting in
h = 124.694 m
So height of ramp = 124.694 m