PHYSICS HIGH SCHOOL

A 70.0 kg skier is at rest at the top of a 120m hill. Assuming friction is negligible.A) What is the speed of the skiers at the bottom of the hill?

Answers

Answer 1

Answer:

Answer:

49 m/s

Explanation:

Initial potential energy = final kinetic energy

PE = KE

mgh = ½ mv²

v = √(2gh)

v = √(2 × 10 m/s² × 120 m)

v = 49 m/s

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A sled with rider having a combined mass of 110 kg travels over the perfectly smooth icy hill shown in the accompanying figure. How far does the sled land from the foot of the cliff?

Answers

The sled land is "25.531 m" far from the foot of the cliff.

According to the question,

The velocity of the top = $V_t$

then,

→ $0.5 \ Vt^2-0.5 \ Vi^2 = -mgh$

→ $0.5 \ Vt^2 = 0.5 \ Vi^2- 9.8* 11$

→ $0.5 \ Vt^2 = 0.5 \ Vi^2- 107.8$

→ $=17.04 \ m/sec$

Now,

The projectile motion in horizontal direction,

→ $S_y = 11 = ut-0.5 \ gt^2$

$= 0-0.5* 9.8 \ t^2$

or,

→ $S_x = 17.04* 1.498$

$= 25.53 \ m$

Thus the above answer is the correct one.

Learn more:

brainly.com/question/13027204

Find the speed the sled has at the top of the hill from the law of conservation of mechanical energy. Equate the kinetic energy at the bottom of the hill to the kinetic plus potential energy at the top :

0.5mv₀² = 0.5mv² + mgh
v = √[v₀² - 2gh]
= √[(22.5m/s)² - (2 x 9.80m/s² x 11.0m)]
= 17.0m/s

From the time independent kinematics equation, find the vertical component of the sleds final velocity (note that the vertical component of the sleds initial velocity is zero) :

v² = v₀² + 2gΔy
= 0 + 2(-9.80m/s²)(-11.0m)
= -14.7m/s (select the neg root, because motion is downward)

With this you can find the time vertically which is the same horizontally :

v = v₀ + gt
t = (v - v₀) / g
= (-14.7m/s - 0) / -9.80m/s²
= 1.50s

Now, the horizontal distance is :

Δx = (v₀ + v)t / 2
= (17.0m/s + 17.0m/s)1.50s / 2
= 25.5m

tell me if you need more help :)

A negatively - charged object has an excess of ?

Answers

The object has an exes amount of electrons

Which of the following best describes a direct current

Answers

Direct current-is the unidirectional flow or movement of electric charge carries(which are usually electrons.

its an unidirectional flow of electric charge

hope this helps!

A driver in a Volkswagen bug (mass = 1335 kg) pulls out going 10 miles per hour in front of a Ford pickup truck (mass = 2675 kg) which is traveling 40 miles per hour. The two vehicles experience a head-on collision. Which of the following statements is true concerning the forces that each vehicle (and driver) experience in this collision? a. The Volkswagen bug experiences a much greater force than the Ford pickup truck due to the greater speed of the truck.
b. The Volkswagen bug experiences a much greater force than the Ford pickup truck due to the larger mass of the truck.
c. The Volkswagen bug experiences a force that is the same as the Ford pickup truck experiences.
d. The Volkswagen bug experiences a much smaller force than the Ford pickup truck due to the smaller speed of the Volkswagen bug.
e. The Volkswagen bug experiences a much smaller force than the Ford pickup truck due to the smaller mass of the Volkswagen bug

Answers

Answer:C

Explanation:

Given

mass of Volkswagen $m_1=1335 kg$

speed of Volkswagen $v_1=10 mi/hr$

mass of Ford pick up $m_2=2675 kg$

speed of ford pick up $v_2=40 mi/hr$

When two bodies collide head-on then force experienced by both the bodies will be the same but opposite in direction.

According to newton's third law, the force exerted by one particle on another is equal to the force exerted by the second particle on first.

Thus two bodies will experience the same force

Answer:

c. The Volkswagen bug experiences a force that is the same as the Ford pickup truck experiences.

Explanation:

Given:

mass of Volkswagen bug, $m_v=1335\ kg$

speed of Volkswagen bug, $v_v=10\ mi.hr^(-1)$

mass of Ford pickup, $m_f=2675\ kg$

speed of Ford pickup, $v_f=40\ mi.hr^(-1)$

Since both undergo a head-on collision they both face the equal impact in accordance with the Newton's third law of motion which states that every action has equal and opposite reaction.

So the bug the force applied by the bug on the pickup is equal to the force applied by the pickup on the bug. This happens only till both the masses are in contact with each other.

HELP NEEDED! Determine the mechanical energy of this object: a 1-kg ball rolls on the ground at 2 m/s. A. The ball is on the ground, so the mechanical energy is zero.
B. 2 J
C. 1 J
D. 4 J

Answers

The mechanical energy of an object is the sum of its potential and kinetic energy.

Because the ball is on the ground, its potential energy is 0.
Its kinetic energy is given by:

K.E = 1/2 mv²
K.E = 1/2 x 1 x 2²
K.E = 2 J

Mechanical energy = 2 + 0
Mechanical energy = 2 J

The answer is B.

I think it's 2 J. Hope I helped :)

Imagine that a tank is filled with water. The height of the liquid column is 7 meters and the area is 1.5square meters (m2
). What's the force of gravity acting on the column of water?
A. 73,500 N
B. 102,900 N
C. 68,600 N
D. 110,700 N