1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Lelu [443]
3 years ago
8

An object is thrown up at 20m/s if it hits the ground after 10s,determine the final velocity and the height

Physics
1 answer:
dangina [55]3 years ago
5 0

1) The final velocity of the object is -78 m/s (downward)

2) The final height of the object is -290 m

Explanation:

1)

When the object is thrown up, it follows a free fall motion, subjected only to the force of gravity (that pulls the object downward). Therefore, the object has a constant acceleration

g=9.8 m/s^2

towards the ground (acceleration of gravity).

Since this is a motion with constant acceleration, we can use the following suvat equation:

v=u+at

where

v is the final velocity

u is the initial velocity

a = g is the acceleration

t is the time of flight

In this problem we have:

u = +20 m/s (taking upward as positive direction)

t = 10 s is the time of flight

g=-9.8 m/s^2 (downward, so negative)

Solving for v, we find the final velocity:

v=20+(-9.8)(10)=-78 m/s

2)

For this part of the problem, we can use another suvat equation:

s=ut+\frac{1}{2}at^2

where

u is the initial velocity

a is the acceleration

t is the time

s is the displacement of the object

In this problem,

u = +20 m/s

t = 10 s

g=-9.8 m/s^2

Substituting, we find the final position of the object with respect to the initial position:

s=(20)(10)+\frac{1}{2}(-9.8)(10)^2=-290 m

Learn more about uniform accelerated motion:

brainly.com/question/9527152

brainly.com/question/11181826

brainly.com/question/2506873

brainly.com/question/2562700

#LearnwithBrainly

You might be interested in
Two cars are traveling along a straight line in the same direction, the lead car at 25 m/s and the other car at 35 m/s. At the m
Phoenix [80]

Answer:

a. t_1=12.5\ s

b. a_2=-13.61\ m.s^{-2}  must be the minimum magnitude of deceleration to avoid hitting the leading car before stopping

c. t_2=2.5714\ s is the time taken to stop after braking

Explanation:

Given:

  • speed of leading car, u_1=25\ m.s^{-1}
  • speed of lagging car, u_{2}=35\ m.s^{-1}
  • distance between the cars, \Delta s=45\ m
  • deceleration of the leading car after braking, a_1=-2\ m.s^{-2}

a.

Time taken by the car to stop:

v_1=u_1+a_1.t_1

where:

v_1=0 , final velocity after braking

t_1= time taken

0=25-2\times t_1

t_1=12.5\ s

b.

using the eq. of motion for the given condition:

v_2^2=u_2^2+2.a_2.\Delta s

where:

v_2= final velocity of the chasing car after braking = 0

a_2= acceleration of the chasing car after braking

0^2=35^2+2\times a_2\times 45

a_2=-13.61\ m.s^{-2} must be the minimum magnitude of deceleration to avoid hitting the leading car before stopping

c.

time taken by the chasing car to stop:

v_2=u_2+a_2.t_2

0=35-13.61\times t_2

t_2=2.5714\ s  is the time taken to stop after braking

7 0
3 years ago
3. What exerts a greater force on the table of 2 kg book lying flat or a 2 kg book on its
Darina [25.2K]

Answer:

A book on its side exerts a greater force.

Explanation:

Pressure = Force / Area

Assuming that 1kg = 10N

2kg = 20N

Area of book lying flat = 0.3m × 0.2m

                                     = 0.6m²

Pressure of book lying flat = 20N / 0.6m²

                                            = 30Pa (1 s.f.)

Area of book on its side = 0.2m × 0.05m

                                        = 0.01m²

Pressure of book on its side = 20N / 0.01m²

                                               = 2000Pa (1 s.f.)

Since 2000Pa (1 s.f.) > 30Pa (1 s.f.), a book on its side applies greater pressure than lying flat.

5 0
2 years ago
To aid in the prevention of tooth decay, it is recommended that drinking water contain 0.800 ppm fluoride, F−. How many grams of
Leviafan [203]

Answer:

2.23 × 10^6 g of F- must be added to the cylindrical reservoir in order to obtain a drinking water with a concentration of 0.8ppm of F-

Explanation:

Here are the steps of how to arrive at the answer:

The volume of a cylinder = ((pi)D²/4) × H

Where D = diameter of the cylindrical reservoir = 2.02 × 10^2m

H = Height of the reservoir = 87.32m

Therefore volume of cylindrical reservoir = (3.142×202²/4)m² × 87.32m = 2798740.647m³

1ppm = 1g/m³

0.8ppm = 0.8 × 1g/m³

= 0.8g/m³

Therefore to obtain drinking water of concentration 0.8g/m³ in a reservoir of volume 2798740.647m³, F- of mass = 0.8g/m³ × 2798740.647m³ = 2.23 × 10^6 g must be added to the tank.

Thank you for reading.

4 0
3 years ago
A car travels from point A to point B, moving in the same direction but with a non-constant speed. The first half of the distanc
Dmitrij [34]

Answer:

Explanation:

From A to B

distance traveled with velocity v_1  in time t_1

\frac{d}{2}=v_1t_1----1

from B to C

distance traveled is 0.5 d with v_2  and v_3  velocity for half-half time

\frac{d}{2}=\frac{v_2t_2}{2}+\frac{v_3t_3}{2}----2

divide 1 and 2 we get

\frac{1}{1}=\frac{2v_1t_1}{v_2t_2+v_3t_3}

\frac{t_1}{t_2}=\frac{v_2+v_3}{2v_1}

Now average velocity is given by

v_{avg}=\frac{d}{t_1+t_2}

taking t_1  common

v_{avg}=\frac{2v_1t_1}{t_1(1+\frac{t_2}{t_1})}

v_{avg}=\frac{2v_1}{1+\frac{2v_1}{v_2+v_3}}

v_{avg}=\frac{2v_1(v_2+v_3)}{2v_1+v_2+v_3}  

6 0
3 years ago
What are the similarities & differences between a thermistor and a light dependent resistor in physics?
viva [34]

An LDR's resistance changes with light intensity, while a thermistor's resistancce changes with temperature.

In dark, LDR's resistance is large and in the day/light LDR's resistance is small.

At low temperature, thermistor's resistance is large, while at large temperature it resistance is small.

In an LDR Resistance increases as light intensity falls, while in a thermistor resistance falls as temperature falls.

5 0
2 years ago
Other questions:
  • Will the current increase or decrease if you increase voltage?
    13·1 answer
  • Electromagnetic waves differ from the other types of waves because they are
    9·2 answers
  • A 39.7 n object is in free fall. what is the magnitude of the net force which acts on the object? answer in units of n.
    15·1 answer
  • A 5 meter long ladder leans against a wall. The bottom of the ladder slides away from the wall at the constant rate of 1 3 m/s.
    5·1 answer
  • A 125-kg merry-go-round in the shape of a uniform, solid, horizontal disk of radius 1.50 m is set in motion by wrapping a rope a
    6·1 answer
  • Compasses line up with magnetic fields. A compass will line upA. Parallel to magnetic field lines, with the south pole pointing
    13·2 answers
  • An object with a mass of 2.0 kg accelerates 2.0 m/s 2when an unknown force is applied to it. What is the amount of force?
    8·1 answer
  • Suppose the tank is open to the atmosphere instead of being closed. how does the pressure vary along
    13·1 answer
  • When melting of a metamorphic rock occurs, it changes into what?
    9·1 answer
  • I need help with this
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!