Two hockey players are about to collide on the ice, One player has a mass of

castortr0y [4]

Because the elevator moves at a constant speed, it's in equilibrium and the net force acting on it is zero. Then the tension in the cable exactly equals the magnitude of the elevator's weight, which is

(3000 kg) (9.80 m/s²) = 29,400 N

3 0

2 years ago

A soccer player icks a rock horizontally off a 40m high cliff into a pool f water if the player hears the sound of the splash s

Semenov [28]

Answer:

v = 9.936 m/s

Explanation:

given,

height of cliff = 40 m

speed of sound = 343 m/s

assuming that time to reach the sound to the player = 3 s

now,

time taken to fall of ball

$t = \sqrt{\dfrac{2s}{g}}$

$t = \sqrt{\dfrac{2\times 40}{9.8}}$

t = 2.857 s

distance

d = v x t

d = v x 2.875

time traveled by the sound before reaching the player

$t_0 = t - t_{fall}$

$t_0 = 3 - 2.875$

$t_0 = 0.143 s$

distance traveled by the wave in this time'

r = 0.143 x 343

r= 49.05 m

now,

we know.

d² + h² = r²

d² + 40² = 49.05²

d =28.387 m

v x 2.875=28.387 m

v = 9.936 m/s

7 0

3 years ago

When a gas is heated, it absorbs 196 joules of heat from the surroundings. At the same time, the gas expands, doing pressure-vol

timurjin [86]

Answer:

(a) q positive; w negative.

(b) ΔE = -126 J

(c) E and ΔE

Explanation:

(a) Determine whether the amounts of heat (q) and work (w) exchanged should have positive or negative signs. heat (q) positive negative work (w) positive negative

By convention, when the system absorbs heat from the surroundings, its sign is positive, that is, q = 196 J.

By convention, when the system exerts work on the surroundings, its sign is negative, that is, w = -322 J.

(b) Calculate the change in internal energy (ΔE) of the gas. J

The change in internal energy (ΔE) can be calculated using the following expression.

ΔE = q + w

ΔE = 196 J + (-322 J) = -126 J

(c) Determine whether one or more of the following is a state function:

internal energy (E) of a system,

change in internal energy (ΔE) of a system,

heat (q) absorbed or released by a system,

work (w) done on or by a system.

E and ΔE are state functions (they only depend on the states of the gas), whereas q and w depend on the trajectory.

7 0

2 years ago

A television of mass 12 kg sits on a table. The coefficient of static friction between the table and the television is 0.83. Wha

Zinaida [17]

The normal reaction between the television and the table is
N = 12 × 9.8 m/s² = 117.6 Newtons

But the static coefficient of friction is μ = 0.83

When the television is about to slide on the table, the applied force should overcome the force due to static friction;
Thus; the applied force should be at least
F = μN
= 0.83 × 117.6 N
= 97.608 Newtons
Therefore; the minimum applied force will be 97.6 Newtons.

4 0

3 years ago

Read 2 more answers

Please help me out someone nothing helping me out please someone

Zolol [24]

Well i think the best answer would be A

8 0

3 years ago