Answer:
The work done is -176.4 J.
Step-by-step explanation:
Given that,
Mass = 1.0 kg
An elevation of 2 m to an elevation of 20 m.
Suppose, Find the work done by the gravitational field of the earth?
We need to calculate the force
Using formula of force
![F=mg](https://img.qammunity.org/2021/formulas/physics/middle-school/rcrgo07k7a6rjryhi8k5pstkr9aa31xtgi.png)
Put the value into the formula
![F=1.0*9.8](https://img.qammunity.org/2021/formulas/physics/high-school/1p8r7dlii91dxgvmkzi4773wu31wklyknx.png)
![F=9.8\ N](https://img.qammunity.org/2021/formulas/physics/high-school/pi5u0n9hcjq93qwe32c3t1n7qtzqa22mc5.png)
We need to calculate the displacement
Using formula of displacement
![Displacement = s_(2)-s_(1)](https://img.qammunity.org/2021/formulas/physics/high-school/hr75m55101u342h5mwbmlfmc2mshga0ocj.png)
![s=20-2=18\ m](https://img.qammunity.org/2021/formulas/physics/high-school/au2fwrfjog72275m2eli52h00635eac32k.png)
The direction of displacement is upward.
Since gravitational force is downwards and displacement is upwards,
Then the angle is 180°.
We need to calculate the work done
Using formula of work
![W=f\cdos s\cos\theta](https://img.qammunity.org/2021/formulas/physics/high-school/c2hgak64z9v8nn1sxez49mkpy4j0xuj1tt.png)
![W=9.8*18\cos180](https://img.qammunity.org/2021/formulas/physics/high-school/3d4twle8wbpxt7eccdeql69yb48scq9u8f.png)
![W=-176.4\ J](https://img.qammunity.org/2021/formulas/physics/high-school/d3nw7dxrkxmv9vldbleyw96b1dr7skn7q4.png)
Hence, The work done is -176.4 J.